Bookstores are retailers. And there are many other retail establishments that sell books, but most authors ignore them. Examples are airport stores, supermarkets, gift shops, discount stores and specialty stores, and you can increase your sales by selling through them.
The good news is that you already know how to do it, since most retailers operate the same way as bookstores. You work through a distribution partner, and books are placed on shelves for sale. Here are some things you can do to compete and grow profitably selling through other retailers.
Define your prospective buyers. Using the 5 Ws technique Define who they are, where, when, why and what they buy. Knowing where and when they shop will lead you to the appropriate retailers.