If your book is not selling the way you expected, and you have already ruled out the cover and the blurb, there is a good chance the problem is discoverability. Specifically, keywords.
Most authors treat keywords as a checkbox. They fill in the seven boxes KDP provides, type in some terms that feel relevant, and move on. That approach usually does not work. Not because keywords are complicated, but because most authors pick the wrong ones.
Here is what actually happens with Amazon search, why obvious keywords are almost always a mistake, and a three-source method for finding the terms readers are actually typing.
How Amazon Search Actually Works
Amazon runs on an algorithm called A9. It determines which books appear when a reader types something into the search bar. The ranking factors are keyword match, sales velocity, and reviews.
Keywords are the entry point. If your book does not match the search term, you are not in the results. Sales velocity and reviews do not matter if you are not showing up at all.
This is why keyword selection is not a minor detail. It is the gate. Everything else you do to improve your Amazon presence depends on your book being findable in the first place.
Why Obvious Keywords Are a Trap
The first instinct most authors have is to target the most popular terms in their genre. If you write cozy mysteries, you type in ‘cozy mystery.’ If you write military thrillers, you type in ‘military thriller.’
The problem is that these terms are dominated by authors with tens of thousands of reviews, years of sales history, and marketing budgets that dwarf what most independent authors can spend. A9 rewards sales velocity. Books that already sell well continue to rank for high-volume terms. New books and mid-list books almost never break through on those terms regardless of how relevant they are.
The authors who actually get found are targeting phrases readers type when they are looking for something specific. Not ‘mystery novel.’ Something like ‘cozy mystery set in a bookshop’ or ‘amateur sleuth series small town England.’ These phrases have real search volume and far less competition. A book with 200 reviews can rank on a specific phrase where it would be invisible on a broad one.
The 3-Source Keyword Research Method
There is no single tool that surfaces all the right keywords. The best method combines three sources, each of which finds terms the others miss.
Source 1: Amazon Autocomplete Mining
Go to Amazon and start typing a search term. Stop before you finish and look at the dropdown suggestions. These are real searches Amazon is showing you because actual readers typed them. They are ranked by frequency.
Work through variations systematically. Start with your genre, then add qualifiers: setting, tone, protagonist type, themes, time period. Each variation produces a different set of autocomplete results. Screenshot or copy every suggestion that could apply to your book. Do this across multiple starting phrases. You will usually find dozens of viable terms in an hour.
Source 2: Competitor Also-Boughts Analysis
Find the books that are most similar to yours and that are selling well. Go to each book’s Amazon page and scroll to the ‘customers also bought’ section. The books that appear there are the ones Amazon has algorithmically linked to yours. Look at their keywords, subtitles, and description language.
This tells you what terms Amazon associates with books like yours, which is more reliable than guessing. Authors who are already ranking have figured out what works. You are reading the evidence they left behind.
Source 3: Reader Forum and Review Language
Go to the places readers actually talk about books. Goodreads reviews, Reddit communities like r/suggestmeabook and genre-specific subreddits, Facebook reading groups. Pay attention to how readers describe books they loved.
Readers do not use marketing language. They use search language. When a reader says ‘I loved this because it felt like a cozy mystery but with a darker edge,’ that is a keyword phrase. When they say ‘perfect for fans of Agatha Christie who want something more modern,’ that is another one. Collect this language. It will surface terms no tool would generate.
How to Evaluate a Keyword Before Using It
Not every term you find is worth targeting. Before you use a keyword, check two things.
First, search the term on Amazon and look at the top results. Are the competing books similar to yours? If the top results are completely different genres or formats, the term may mean something different to readers than you think.
Second, look at the sales rank of the books ranking on that term. If every result is ranked above 10,000 with thousands of reviews, the term may be too competitive. If you see books in the 50,000 to 200,000 range with modest review counts, that is a term where a well-optimized new book can compete.
Free tools like Publisher Rocket (paid) and the Amazon search bar itself will show you search volume signals. The goal is not the highest-volume term. It is the best ratio of volume to competition for your specific book.
Where Keywords Live Beyond the 7 KDP Fields
Most authors know about the seven keyword fields in KDP. Few use all the other places where keywords carry weight.
Title and subtitle. Amazon indexes every word in your title and subtitle. A subtitle that includes specific keyword phrases will help your book rank for those terms even if you do not use them in your keyword fields.
Series name. If your book is part of a series, the series name is indexed. Including genre-relevant language in your series name (within reason) adds keyword real estate.
Book description. Amazon’s algorithm reads your description for keyword signals. This is separate from reader-facing copy. You can write a description that serves readers first and also naturally incorporates the terms you are targeting.
When you combine strong keyword fields with a keyword-rich subtitle and description, you multiply your surface area for discovery without any additional advertising spend.
A Keyword Audit for Your Existing Books
If you have books already published, the keyword audit is often faster than starting from scratch.
Go through your current seven KDP keywords. For each one, search Amazon and see where your book ranks. If your book does not appear on page one, the keyword may be too competitive, or the term may not match your book well enough to rank.
Next, run the three-source method on your existing book. Compare what you find with what you currently have. You will almost always find specific phrases you missed that are relevant, searchable, and achievable.
Prioritize changes with the highest expected impact. A single high-specificity keyword that actually matches reader search behavior can move a book more than six generic ones.
The quickest wins are usually specific phrases with real search volume where the current top results are weaker books. Find one or two of those per book and the work pays for itself.
A Note on Keywords as Ongoing Work
Keywords are not a one-time setup. Reader search behavior shifts. New books enter the market and compete for terms. Trends in genre naming evolve.
Authors who consistently sell treat keyword research as a quarterly task, not a launch task. They check what is ranking, update underperforming fields, and use the language readers are currently using.
The authors who feel like they have tried everything and nothing works have usually done this once and then stopped. The authors who keep finding new readers are the ones who keep looking.
Your book is findable. You just need to find the right door.
