How to search the entire catalog

Question: I've got loads of folders in my library, and they span over several pages on the Folders section in the Library module. But, when I want to search for a photo using the Library filter, I need to always first, move my mouse and click manually over the Folders section to the top Parent folder before I can do a search on the entire catalog.

I was wondering how you go about searching the entire catalog, but with a quicker solution? I don't want to always have to find the most parent folder and click on it before I do a search across the entire library.

Thanks in advance!