Search in a multidiscplinary database or one that is discipline-specific using keywords that might appear in titles or abstracts to identify articles that have used qualitative methods. Some terms you may consider:
Using an asterisk (*) after a term tells the database to search for variant endings of the word. For example, observation* will include results with the terms observation, observations, or observational. A search in a database may look like this:
A small number of databases that include filters specific to methodologies will allow researchers to more readily limit their results by a method of interest.
PsycINFO has a Methodology filter that can be found at the bottom of the database's search homepage or on the left-hand side of the search results page. You may need to scroll to locate it in both places
PubMed can filter search results by a particular method using "Additional Filters" on the left-hand side of the search results page. Look through Article Types to see if the method of interest is included.
Some databases come equipped with standardized terminology built in where all items that appear in a database are described using a standard word. This standard vocabulary can be called different things in different databases--subject headings, descriptors, thesaurus--but invariably serve the same purpose of describing an item in a standard way. This allows researchers the ability to easily manipulate a search to quickly pull back similar or related items without having to know all the ways that item could be referred to.
You can check to see if a database offers a searchable list of subject headings, and in most cases (but not all), this thesaurus or list will be located in the toolbar that runs along the top of the database search.
There are some instances where you may need to dig a little to find a database's index of subject headings or assigned topics.