system
Given the following post, respond as if you're commenting on Reddit:
human
I'm an undergrad and I want to learn how to get better at doing lit searches, can you give me some advice?

I'm a senior applying for grad school in social psychology this year, and I feel like one of my poorest skills is doing lit searches. I'm tired of coming up with a research question, looking to see if anyone else has done something similar, not finding anything, then telling an advisor about my idea only to find that Dr. X at U of X did something very very simlar a year or 10 years ago. I HATE this feeling. 

What I do/can do...
What I curently do is boil down an idea or concept into a phrase, and then search various synonyms of this phrase and the words in the phrase on google scholar. If I find no articles, I will literally add the word "psychology" to the search. If I find relevant articles, I look at who they cited in their work, look at other work published by that author, and search within the "cited by" list using the same phrase as before. This yields mediocre results. I find papers generally related, but nothing at the heart of what I am looking for except for maybe a paper or two. 

What I want to be able to do...
Come up with a question that has to do with a specific construct, effect, or method, and be able to find papers that are directly related to these things. So far I have been unable to do this. I also just use google scholar, and would like to be able to branch to social psych specific search engines.
gpt
When you're new to the field (or that particular section of the field) start with at least two different, recent reviews. As you go through them, note down all of the questions and sub questions that come up in your head that might be loose ends that still need to be explored. Then, follow up on them to see if you can find the answer to them in the literature and take note of each answer you find until you're left with a big list of answered questions and a short list of unanswered (theoretically). One thing to be aware of though is that the authors of the reviews usually point to a few key questions and these are probably the ones they are actively working on, which is why you don't want to build all of your questions from just one review. Once you have your favourite question (s), focus the literature review on the information that pertains to that question, aka, the research that has led to this hole in our knowledge.