Method One: Use a subject heading from an article you have.
Find an article you have found particularly useful for your research topic. The website you accessed it on (ProQuest, Ebsco, etc.) will contain that list in the article's abstract and details page. They may be called controlled vocabulary, subject terms, subjects, keywords, or headings. Click on one of the subject headings to be taken to all items with that heading.
Method Two: Search or browse for a subject heading.
Many database providers contain ways to search subject headings. EBSCO and ProQuest both have methods of browsing and searching for a subject heading.
In ProQuest, use "Advanced Search," "Thesaurus," select a thesaurus, and then search using the search box at the top of the page.
In EBSCO, the top banner will have a link called "subject headings." Clicking on this will take you directly to a list of subject headings, with a search box to search only for headings.
Example of tags vs. subject headings
On social media websites, anyone can "tag" any picture or post with any tag, using any word or phrase, even if the tag is irrelevant to the content. Users then click on the tag, expecting more content on tagged with that topic. However, they may have several tags to search for on the same subject, and everything using a tag may not be relevant.
In a scholarly database, subject headings are like sophisticated tags. Each database has their own list of approved tags (subject headings). Librarians, when cataloging these papers, only use those already established subject headings to tag the papers. They select the tags based on the content of the paper.
Subject headings are changed or added to fairly regularly. For instance, retarded children may have been an acceptable term in previous years, but now the term might be children wih developmental disabilities. Additionally, as more topics, phenomena, or events occur, more subject headings are added reflecting these new developments.
What is a subject heading?
A subject heading is a searchable tag specifically chosen to represent a specific idea or topic that can be said in many ways.
In the English language, there are several different words that communicate the same or similar idea. For instance, the idea of a dog can be expressed as dog, canis lupus familiaris, doggy, pooch, man's best friend, or canine. Same concept, very different words.
This doesn't mean any time an author wants to mention a dog, they have to say canine. Instead, a librarian or even the author of a title will assign subject headings using a list of approved words or phrases, and insert them into the information they give the database. These subject headings then become searchable.
Each database has different headings. This makes sense because a medical database would have a controlled tag for lumbar puncture, but not necessarily for transformational leadership. A business database, however, would be vice-versa.
What are thesauris and indices?
A thesaurus is a list of words in a database and how they related to each other. Most commonly, you will find the three following relationships: Broader or narrower, related, and "used for."
BROADER terms are terms that are less specific than a given idea. For instance, a broader term for lotion is skin care.
NARROWER terms are terms that are more specific than a given idea. For instance, envelopes is a narrower term for stationery.
RELATED terms are terms that are commonly used together, possibly worth you checking out, but might not be relevant. For instance, a term related to business maybe marketing.
USED FOR terms are a way to direct you to what the database calls an idea. For instance, if you searched for fairy tales, you may be directed to folklore.