A dog that runs off is usually bored and needs more exercise. Dobermans are working dogs and they need at least one hour and maybe up to two hours a day of exercise.
Also get a LONG rope (50 feet or so.) and let it out and call the dog back . Guide it back with the rope if you need to and when it comes give it an extra yummy treat. Do this for a few minutes every day and the dog will come without the rope.