A syllabus or syllabi is part of the long list of resources considered grey literature. By including the words "syllabus" or "syllabi" along with your keywords search, you can possibly find a syllabus covering your research topic. universities or programs covering your topic of interest. Sometimes you can find entire syllabi or simply a description of a class that includes your keywords. What topics, readings, or other piece of information can the syllabus give you?
If you find a course syllabus that covers your topic, see who's teaching the class and what articles they've written. Search their name in TWUniversal, Google Scholar, Web of Science, Scopus, or other databases to see what other articles they've authored or co-authored. Many times researchers are willing to discuss their lines of scholarship with people who reach out and want to discuss their shared topic of interest. See if you can find a contact email on their faculty page and hopefully your conversation can lead to even more information that can benefit your research. Remember to cite the conversation or email if use the conversation in your paper.