Narrow Your Topic Down to Key Ideas
Search indexes return better results if you use keywords, not sentences or questions.
If your keyword is two words like "Appalachian Trail," use quotation marks to search a phrase as a keyword.
Add in multiple keywords using AND
Don't Forget to Try Synonyms
For example in addition to ecology, you could try key words like: bionomics, environmental biology
Mine Articles for additional Relevant Keywords
Update your keyword list as you research.