Unlike Google, library databases can't understand an entire sentence. You will need to break your topic down into the most important ideas - the KEYWORDS.
Most words have synonyms that mean the same, or very similar, things. For each keyword in your topic, try to come up with at least one synonym or another very similar keyword. Not all keywords will have synonyms, but many do!
Keyword: green light
Possible synonyms: green aura, green color
Possible synonyms: significance, relevance, emphasis
Sometimes scholars use terms that you might not be familiar with, or which might mean something very specific within the discipline. While searching, look for unfamiliar terms or words that show up a lot. Try searching for those and see if you find more relevant sources.
Most library databases have search tools built in.
Try some of these:
Look on the left and right of your search results, or for an "advanced search" page to find these tools - and more!
Use the operator AND to find only sources that mention your keywords:
Add more keywords in order to focus the results even more:
Use the OR operator to expand your search with additional keywords:
This will find sources that include either word, so you'll see more results than by searching for just one keyword.
A great way to use OR, is to combine it with AND. So, to expand your search results, you could try this:
When you do this, put parentheses around the keywords connected with OR. Now you will have a list of results that all mention green light, and either importance or significance.
If your search results are not what you expect, there are several options you can try.
If your results don't seem to match up with your keywords, try putting quote marks around exact phrases. This will bring back results that only use that exact phrase.
"green light" AND importance
It's always a good idea to make sure that your search terms are spelled correctly. You may also need to try using a different form of a word
Sometimes you just need to ask for help. Some research topics are more tricky than others and getting help from a librarian can save you a lot of time.