The phrase "to deepen one's understanding" means to increase or enhance someone's knowledge, comprehension, and insight about a particular topic or subject. Full definition
We provide expert resume writing tips to help deepen your understanding of what an effective resume sets out to do. (resume-now.com)
I can't begin to tell you how grateful I am, not just for the milestone, but for the countless times you've helped deepen my understanding of games. (brainygamer.com)
We conduct research to deepen understanding about the complex needs of these children and how to help them overcome social, behavioral, and emotional challenges. (child.tcu.edu)