Choosing the right terms will help get the results you're looking for. Keeping track of what you search and where can help save time. Continue to add terms until you have about 30-50 results.
While you're familiar with how to search for material, when working on your thesis, you really want to hone in your skills and return a set amount of results --ideally around 50. This provides a workable number of sources without being too narrow. Using Boolean Modifiers (AND, OR, NOT) can help focus your results. Additionally, Boolean Operators ("quotation marks", (parenthesis), *asterisk). The following videos go into more depth.