Your search for information often begins with an assignment. It is important to make that assignment clear to yourself: what exactly is the intention and what result is expected?
So first you look for the information you need (information demand) and what the framework is. This allows you to quickly determine how broad or in-depth your search will be. Consider the following points:
What is the context in which you are looking for information?
Are you working on a major research project, or do you need to look something up for your internship assignment?
What are the learning objectives for the assignment?
Is the goal to be able to carry out a thorough (literature) research or is it about getting to know a subject?
What will you be assessed on? What are the requirements for your research? This could include requirements for the use of sources.
Who is your target audience (if publication is the goal)?
Are you writing for academics or for secondary school pupils? Are they peers or not?
How extensive should your research paper be?
For a detailed report, you will do more in-depth research than for a short report.
How much time and what resources do you have?
Do you have to hand in the report within three weeks or do you have three months? What resources do you have access to?