A human indexer assigns subject terms to each article, book, and video, using a controlled vocabulary. (This is how most library databases and library catalogs are organized.) Subject headings are basically a strict hashtag system designed to help researchers and students find content faster.
Expert users start with keyword searches, then switch to searching by content.
Manage overwhelming results by only viewing subject-relevant content!
More than 250,000 results is... a lot. There's some good stuff here. But more on-target content and fewer results would help.