A literature review is a critical account of the methodologies and data on your research topic by accredited researchers in the field. The following is a list of search techniques to guide the process:
Identify keywords associated with your topic
Test your keywords by using them in the recommended databases
Are your keywords included in the titles?
If your keywords are not included in the titles, search MeSH to determine what keyword(s) to use
Also, identify author supplied keywords in the relevant articles you find