The e-commerce site I am working on currently only has a search bar in the header. We are adding a "Shop By" dropdown in the header where customers can select different categories to browse by. The problem now is figuring out how those two functions interact.
I've been told repeatedly that if a customer selects to "Shop By" a category, they will then be drawn to perform a search, and expect their search results to be filtered by the category they had previously chosen.
I can provide two different examples. On Etsy, if you select to Browse by, for example, Art, you are taken to a page with art-related products. If you then perform a search, that search is performed in All Categories, and you can filter from there. On Amazon, you can shop by department - and when you select a department, it shows up on the search bar and your next search will be just within that department.
On our site, selecting to shop by a category simply takes them to a search page that filters products by the selected category. When should we choose to maintain the pre-selected filters, and when should we start a brand new search for the user? How can we predict what our customers will want to see?