Thank you both for the advice.

Clara 4457: Yes, they tried to comb him, but he didn't let them to work on his very long coat. I will talk more with people at the shelter about it, and am willing to even pay for the shaving you suggested; i think with a better "do" his chances to be adopted will be higher. I "claw" his head and body with my nails, he doesn't seen to be bothered.
Yes, one year is a very long time to wait for a new home, poor Strolchi (his name).

Also happens that the shelters here (also in Germany) have many stray dogs coming from Greece, Italy, Spain, East-Europe, due to tourists that bring them out of pity, and some times they do not adjust to a new life. Sometimes these shelters help the shelters from those countries, wich are always over poppulated. I do not know if Strolchi is one of them. There are dogs that are there even longer, specially the old, blind, or with age related infirmities.

Scooby Doo Doo: The way you do with your Chihuahua mix reminds the mothod my mother used to do WITH ME to extract pimples from my face in my pre-teen years LOL.

If the shelter manager allows Strolchi to be shaved, i will follow your suave method to introduce him to the brush.

Thank you both very much. Your suggestions complement one another: first shave, then get used to the brush!