If you’re in need of more sources for your thesis or dissertation, check the university staff pages of the seminal theorists and thinkers in your field to see what journals they have published in.
I just checked out communications scholar Theo Van Leeuwen’s staff page at the University of Technology in Sydney, Australia. Having published in close to 30 different journals, Van Leeuwen’s list of publications is quite helpful and very impressive!
Also, when you’re searching for articles, be creative with keywords.
Think of all the different ways your research topic could be categorized. For example, for my research on the branding of English in South Korea, I have used a wide range of search words, including: commodification, Korean, brand, multimodality, communication, education, and globalization.
Be imaginative and resourceful, and most importantly, have fun!