Dogs when wet give off a distinctive pong and at other times can smell like stale biscuits. You'll never get rid of it completely but it can be mitigated. What it is fed on can make a difference, where it walks and how often it is brushed and cleaned. If a dog pongs strongly then either it has rolled in something (fox poo is particularly unpleasant but dogs seem to like rolling in it) or there is something wrong with it and a vet ought to examine it. Ear infections can cause an unpleasant smell as can skin problems.
Vacuum frequently, clean the dog bedding and dog towels regularly and perhaps use something like fabreeze.
In the 40 years of keeping dogs we've never had a major smell problem unless they have rolled.