Masters Thesis student looking for an apartment

I am Dominik, a 25 year old Molecular biology student at faculty of science, University of Zagreb in Croatia and a former chef and a nutritionist technician. I am enrolled in an exchange program during which I will be performing my Masters thesis work in one of the laboratories at Max Planck Institute for Development Biology in Tübingen. To that end I would need a place to stay during the course of my internship.
I am very quiet, non smoker and very tidy and organized.
It is important to me that the apartment is located within 40 minute (give or take) walk from Max Planck complex.
I would require accommodation from March/April to 31st of August.