When you do a search in Google Drive you search for more than just the title of the document. Google searches the entire body of the document. Thus when I do a search for “parabola” any document that mentions “parabola” anywhere in the document will be returned in the search results.
If you know the title of the document contains a keyword you can filter your search by typing title colon and then the keyword. No spacebars!
If you want to search a group of keywords you will want to place those keywords in quotations. Note that it will search for exactly that phrase. “common core” will not return the same results as “core common.” It will also not return anything with extra words in between the keywords.
title:”common core” will return documents titled “You and the common core an essential guide.” It will not return documents titled “Get to the Core of Common Practices.”