Are There Ways to Identify Which Subsample of Data an XGBoost Tree Was Fitted On?

Hello, I’m currently working on my undergraduate thesis related to XGBoost. In my thesis, I need to explain in detail the processes behind XGBoost training, ranging from how it builds trees to calculating leaf weights, etc. My question is, since I have set the subsample to 0.7, meaning that each tree randomly selects that portion of the training set on which to train, is there a way to see which samples were randomly selected for each tree? Thank you.