Search engines like Google us 'bots' or 'spiders' to seek out pages on the Internet and index them, so when you search Google finds the right page. While Google is great at finding local sushi restaurants, items like library databases are restricted by their license and they will not show up in your search.
The library’s search engine (Search Everything) and its databases search for the books, articles etc., that the library has purchased. They search by relevance of your keywords. This is why choosing different words is important as the author might be using the synonym of your keyword.
You will not find everything you need in one search. You have to try different words and search strategies and different library search tools (e.g databases).
Listing or mapping out your keywords and related terms at the beginning of your search will save you time.
Another technique is to notice the terms being used by the sources you do find. Use those terms in your next search.
From Seneca Libraries (Open Captions)