[T]he writing of a literature review is ultimately a creative activity into which the writer has an enormous input. (Oliver, 2012, p. 59)
Systematic reviews must include the thorough search strategies used to collect the material of the review for reasons of transparency and reproducibility. Whether you're doing a systematic review or not, the structure of the search can be very useful to help you think about how to do your own research. Find some examples below, or if you need help thinking it through, contact a librarian!
Later analysis will reduce your total number; a rigorous selection/inclusion process is key to a good review
It may feel that there are always more sources to track down, and in the case of a field that's rapidly developing, that may be true! However, your paper has to be completed eventually, so your search plan has to include the point at which you stop collecting new citations.
Another way:
Scite and Semantic Scholar are two tools that utilize artificial intelligence to show how citations are used in context: not just that they're cited in a paper, but how and why they're used in that paper, such as whether the use is positive, negative, or neutral, or how much of the citation is referred to.
However, keep in mind that not all articles will be available in full-text to be analyzed in the AI tools, as the content both tools analyze is so far based on citations available outside of copyright restrictions.