Subject headings are a set of terms or phrases that are used in libraries to describe, classify and organize books, articles, digital and other content. Subject headings are pre-defined, they form a controlled vocabulary, so not all words are subject headings.
You can use subject heading thesauri to help you select the most appropriate terms for your search. With the help of thesauri you can easily choose alternative terms, narrower or broader terms which will affect your search results. Here are a few examples of thesauri:
Searching Tip: You can also start your search with natural language keywords. Browse the search results. Once you’ve found a few relevant articles, check the subject headings that are used in those articles. Note them down and redo your search using to subject headings you found. This should give you more accurate search results.