you haven't said what are you intending to do your post doctoral in ?
Yes, this is the good question.
It is difficult to help, because I don't know what methods and techniques will be learned. But you cna probably do a great job with this.
You want to learn research methods and techniques, and these methods and techniques will be useful in the work you will do in Iraq. So, I think you should search the internet for information about quantitative and qualitative research methods. Read about survey research, case studies, causal correlational, experimental, and so forth. Google this:
quantitative, qualitative, research methods, list
Read about various research methods. You can learn about all of them in college, so all you need to do is read online about the various methods. When you see one that will be USEFUL FOR DOING THE WORK YOU WANT TO DO IN IRAQ, that is the one to write about.
So, this does not have to be all about the school in Germany. It can be about research methods you would like to use in your home country.
:-)