Unlike Google Scholar, most databases will treat a string of keywords as a specific phrase, so entering "interest groups elections" may not be the best way to search. To combine your keywords and phrases, you need to use what are called Boolean operators.

Boolean operators are simply the words AND, OR, and NOT. They help you broaden (find more) or narrow (find fewer, more relevant) your search results.

The Boolean operator AND helps combine keywords and phrases to find where the terms intersect. The AND operator narrows your search to retrieve only those articles containing both the phrase interest groups and the word elections.

In this example, one light blue circle represents all the articles that contain the phrase interest groups and the other represents all the articles that contain the word elections. The dark blue represents the results from your search - only those documents that contain both of the search terms you are looking for.