We’ve already seen that your job in the literature review
is to make the case for your research. You do that by highlighting any gaps in our existing understanding. That requires you to start relatively broad, and zero in on your particular niche and topic. That’s because you’re going to have to contextualise and situate your study in the wider literature.
Think of a funnel. You start with the broader topic, and then as you go through the review you zero in in more and more detail until you are focusing solely on the particular topic of interest.
What that means is that, if you’re struggling to find literature, you’re not far enough up the funnel.
Let’s think of a silly hypothetical example to illustrate this. Imagine that you’re studying how the consumption of strawberry bubble gum affects the performance of English PhD students. That’s super niche and super-specific. Unsurprisingly, there is no literature on the topic. However, you can cast the net a little wider by looking at how the consumption of any form of gum affects the performance of PhD students from anywhere in the world. You’re still not likely to throw up that many results, so you’ll need to move further up the funnel by casting your net wider. So, you might also look for literature that discusses the consumption of gum by students at every level. Or, you could look for literature that discusses the consumption of other substances, such as coffee or tobacco. You might also look at how other stress aids affect the performance of students. You get the idea.
As you broaden the net, you also draw in a wider and wider range of literature. Over time, you have a sufficient amount that you are able to fully contextualise your particular study in a wider academic debate. You’ll need to tell the reader that you’re casting your net in this wide way. That’s fine; be upfront about the novelty of your topic.