Give him a good bath with medicated shampoo and conditioner. Comb his hairs regularly. This might help :)

Procott dog shampoo, gives nice fragrance and stays longer. Consult vet for dandruff shampoo Wipe him everyday after evening walk with soft cloth and savlon Brush his coat everyday for better results.

My dog had dandruff ago , vet gave a injection to him and said to apply coconut oil 15 min before his bath

Before every bath