Teddy's sparse hair may be caused by malnutrition or skin diseases. First, check whether there are parasites or skin diseases on the dog. If there are skin diseases, the dog needs to be dewormed or medicated. In this way, the dog will grow new hair. Pay more attention to the dog's hygiene and dry the hair in time after bathing to avoid the breeding of bacteria and fungi. If it is due to malnutrition, the dog needs to be supplemented with nutrients. You can give the dog Feed the dog some fish oil, lecithin, nutritional paste, egg yolk, chicken breast, fish and other foods.