You should try OpenAI embeddings. They're fairly cheap to run over a large amount of text (should cost <$10 if you have thousands of documents I believe, but correct me if I wrong).
Then you can run searches for content even if the exact words aren't the same.
Like let's say you have a document titled "Measuring canine tooth caries over 2004-2020" and it never once mentions the word "dog".
If you type in "dog" after doing the embeddings, it'll suggest that specific document because "canine" and "dog" are closely related.
Great way to organize large groups of texts, there's plenty of YouTube videos on how to do it, and best of all, you don't have to spend time manually organizing everything. You just let the machine model do it for you.
You could even get it to auto-tag your documents based on what it thinks is the best category for the document and make it easier for you to parse that way as well.