Say that you need to find information about recycling in the context of campus sustainability.
Do you need information specific to a particular school or school program?
Do you need information about recycling in general? Information about recycling on college campuses? Information about battery recycling on college campuses? Information about barriers to battery recycling on college campuses?)
Do you need comparative data over a spread of years?
Do you need to know about the people that initiated the sustainability effort and their agenda? Or do you want to focus on the technologies or practices developed? Or do you want information about strategies that helped people participate in sustainability efforts? Or do you want to focus on the pressing environmental needs that inspired the program? Or do you want to know about the impact of the sustainability effort?
(Wanting to know all of the above is okay, but you may need to use different databases and other resources to find information on distinct areas of interest - and you want to be sure that the need for all of that information is reflected in your research question).