Articles can mean two different types of publications:
Check your research assignment requirements, so you use the right kind of articles for that assignment.
Databases are collections of multiple journals and articles that can be searched all at once. Some databases are general, and some are subject-specific. Some databases include newspaper/magazine articles, but most databases only have journal articles.
Databases are searched using search terms. Search terms are building blocks that you can add together.
Databases usually have multiple search bars that can be used to enter separate search terms. (You might need to click on "advanced search" to see multiple search bars.)
A database is searched by creating a search query. A search query is the combination of search terms, filters, and code that you type or select before clicking the search button.
This is an example of a search in Academic Search Complete:
This is an example of a search in JSTOR:
Turn your research question into search terms.
Look at that article's keywords. Keywords are usually written underneath the article's listing in your search results.
Different databases use different keywords. By reusing the keywords, you are learning to speak that database's "language".
Some databases will give you suggestions for search terms when you start typing in a search box. These are terms that the database absolutely recognizes.
Sometimes, the suggestions will be several terms in the same text box, all separated by the Boolean Operator or. This means that the search engine will search for all those terms at once.
Always check before you select a string of terms. Some of the terms might not be equivalent for your specific research topic!