Finder Problem

Ever since updating my 2020 MacBook Air to the newest OS, Finder can no longer retrieve my documents UNLESS I have recently opened them. For example, if a document is called “Smith et al” and I type that in, Finder will return no results. However, if I manually find “Smith et al”, open it, close it, and then type it into Finder, it will appear. I have followed a number of guides on rebooting Finder and performing other simple tasks to no avail. Anybody know what else I can do? Thank you :)