Depending on your research question, you will want to consult books, scholarly articles, and other media (such as conference proceedings, artifacts, reports, etc).
Do you need background information?
Are you aware of authors for your topic?
Should you limit your results to time periods?
Should you limit your results to a particular region?
Do you want to limit your sources?
What databases should you use?
First think about your topic. Questions to consider:
Example topic: X-ray diffraction
Try X-ray diffraction and mineralogy
Still too broad?
Try x-ray diffraction and mineralogy and a mineral (ex:
Want to go narrower still?
Try x-ray diffractrion and mineralogy and kaolinite and a geographical region (ex: Turkey)