Currently, searches use OR logic on all of your search terms. The more terms you type, the less narrow your search gets.
A more sensible default would be for it to use AND: Requiring all terms to "match" in any displayed results.
Second, at present, the way search terms are matched is super limited. Searches only match terms from the start of words. The minecraft mod NotEnoughScaffold cannot be found with a search for Scaffold. The mod B.A.S.E. is to the best of my ability to tell, completely unsearchable.
Searches being able to match the inside of a word, and not just the start, would be great.
We're planning to expand the search feature as part of our Ux/Ui changes.
Searching for a string within the mod is something we hope to release close to the handover, and later we will look into other search capabilities and options.