I don't think I've ever added the ability to filter via the text field on any search system I've built. Normally there's checkboxes and categories though
Which are often lacking. If I want to search for everything except brand X, I have to check the box for every other brand, which is a hassle. If I'm looking for "pirate costume" and I don't want anything related to One Piece, there's no checkboxes, or anything, to help me.
I've been using Kagi for 2 months and swear by it. It might feel silly paying for a search engine, but I'm now the customer instead of the product, and I can customize my searches the way I want.