FICTION>Mystery Thriller & Suspense>
As there are several sub-categories under Mystery Thriller & Suspense, you can then choose two sub-categories. The following are your choices:-
Mystery Thriller & Suspense
- Police Procedural
- International Mystery & Crime
- Crime Fiction
FICTION>Mystery & Suspense>Police Procedural
Before you make your choices, however, do a bit of research in to how many books are listed on Amazon in the sub-categories you plan to use. To do this, go in to Amazon, click on Kindle eBooks and on the left hand side of your screen you will see a list of categories. If you drill down in these categories, you will then see how many books there are in each sub-category.
For example, at time of writing:-
Police Procedural 4,601
Crime Fiction 26,077
International Mystery & Crime 745
As you can see from the two examples I chose above:-
FICTION, MysteryThrillerSuspense, Police Procedural
FICTION, MysteryThrillerSuspense, Mystery
the sub-category I chose for Police Procedural has a lot less competition with only 4,601 books compared to the Mystery sub-category with 50,825 books in it. If you do happen to have a run on sales, you have a far better chance of obtaining a good rank in a sub-category with fewer books in it.
Therefore, rather than the Mystery sub-category, I would have been better off to choose Cozy that has only 1,486 books.
FICTION, MysteryThrillerSuspense, Cozy
Then again, I could have chosen Crime Fiction that has an extra sub-category:-
FICTION, MysteryThrillerSuspese, CrimeFiction,Murder
Crime Fiction does have 26,077 books , but Murder only has 5,428. Your book will get exposure from both these categories.