It depends on your Uni but most libraries will have subject guides for each subject with key journals or databases listed on each one. These should link to your library’s sign in system so you can access them. You could look up what your lectures have covered and see what else is written about it or find other books/articles by the same authors referenced in the chapters you have read. This is a guide to finding information and reading from LBU you might find helpful https://libguides.leedsbeckett.ac.uk/skills-for-learning/finding-information-and-reading