Looking for a room for a long term stay in Hannover

I am Jingzhong Yang, a 26-year-old Ph.D. candidate from China and now I am searching for a long-term stay place in Hannover Germany in the next few years due to that I am going to study at the Leibniz University of Hannover for my Ph. D career at the beginning of October 2018. In fact, I do not have too many requirements for the place. I hope the location of the apartment can be just a little closed to the university if it is available. Concerning the monthly fee for the house, I hope the rent is not higher than 400 € for warm rent and it would be great if the house is furnished with kitchen, bathroom and so on which satisfies the basic life requirement. Of course, I need the table, chair, and bed. Basically, I think it is not a big issue for me to accept the nach rent. Here I would like to do a short introduction about myself.
First of all, I have the working contract and stable income from my contract so that you do not need to worry about the monthly house rent. For now, I am learning in Dresden Germany because my Ph.D.supersior needs me to be here and I have to go back to Hannover for my official study starting from the October. Moreover, I am a quiet and hard-working student so I take most of my time to work in my office or labs even on weekends. Well, after all, I am learning the quantum optics so that I have to always try hard for it.
By far what I am looking for is an apartment for my stay in Hannover in the near future, you can get in touch with me by email and I can also introduce more about my condition for you.

Best regards
Jingzhong Yang