To search for articles it helps to convert your information need into an answerable question.
There are two basic types of search queries that most databases use: Keywords and Controlled Vocabulary (Subject Headings).
Keyword searching (natural language searching)
With keyword searching you to enter search terms that best describe your question. You also need to include synonyms and variations of the search term to make sure that you have retrieved all of the relevant records.
For example, if you are looking for information on "heart attack" using a keyword search, you should also search using the terms "heart attacks," "myocardial infarctions" and so on.
Subject Headings (controlled vocabularies)
Subject headings are pre-defined, authoritative words or phrases used by some databases to consistently describe and systematically organize content. The hierarchical nature of the lists allow broad concepts to be narrowed in a manner that stays consistent within that terminology.
Before a record is added to a database, its subject matter is determined. Specific terms that apply to those subjects will be chosen from the pre-determined vocabulary list, no matter what terms the author used in the paper. This way, there is a consistent method for retrieving the same information concepts even though different terminology has been used. For example, the term "heart attack" is always listed as "myocardial infarction" within a controlled vocabulary structure, such as MeSH (Medical Subject Headings), the vocabulary used by MEDLINE.
MeSH (Medical Subject Headings) will be covered later in this orientation.
Adapted from Valpariaso University.