It is likely your assignment is asking you to find an article describing research done with a qualitative method. It may also ask for another research method like quantitative or design science or action research. You may also be looking for a particular type of research collection, such as surveys, interviews, or statistical analysis.
In each case, it is possible to add the term to your keywords when searching in the library databases or online.
For more information about research methods, try the library database SAGE Research Methods, which includes resources about how to do research.
