Search engines, like Google, search by keyword. The default search in Orbis, Quicksearch, and Articles+ is also by keyword (or "All Fields"), where you will get results with your keyword is located anywhere in the record or document.
A subject defines a book or an article as a whole, and subject headings link information -- just like how hashtags link conversations in social media (#basslibrary). Using subject headings is an effective way of doing research.
Ways to identify library subject headings:
1. Start with a keyword search in Quicksearch and identify 2 or 3 books that are loosely related to your topic (they don't have to be perfect, just close enough). Open the records and look at the "Subject" field -- voila! Write these subjects down, or click on them (they're hyperlinked!) to uncover other material within that same subject.
2. Some resources will offer the ability to browse subjects, for example:
You can combine your keyword and subject searches by using Boolean operators AND, OR, NOT in an Advanced Search. When combined with keywords and/or subjects, boolean operators will help focus your search in the following ways:
In the example above: