Slow download speed using GRAPH api

I wanted to start a little discussion because I can't find any information about my issue with download speed of GRAPH api.

So Let's start with some information that I have a python app that connect to my One drive Business. I have there two folders with pdf's one is about 70k and one is 7k. I connect to them successfully. I know that this API has some limitation with the amount it can download on one request but still I think it is not fault but my and lack of knowledge. The biggest problem is when I use some search feature in my app that requires searching a specific file(it just freeze my whole app). I make all communication inside my python code and I don't see any room to further optimization. 

I will just mention that this is my first time working with API and clearly don't know where to ask for any help.