Healthy dogs don’t smell if they do it is often due to a health problem. A wet dog smells and this should be the only time that they do. After a dirty walk a dog should have the mud washed off with warm water without using shampoo, then towel dried.
If your dog is washed after a dirty walk and despite regular grooming it still smells, this must be investigated. You must find out where the smell is coming from. Smell its ears, mouth and the anal area and other orifices to establish where the smell is coming from.
Please don’t delay visiting the vet, this will lead to pain and bigger vet bills. Your dog could get abscesses in its ears or anal glands. If it has bad teeth or a gum infection, an extraction may be necessary. Minor problems become major problems it they are neglected.