It is always underestimated that animals have better sense of smell than humans. If you are also one of them then don’t worry as most of the people think the same.
You might see your dog sniffing all around. Dogs doesn’t care what they find: grass, cement, flowers, fire hydrants, poop, trash cans, fences, buildings — it’s all an exciting adventure of scents to them.
In comparison to that of other animals, the human sense of smell is widely considered to be weak and underdeveloped. This is, however, an unproven hypothesis. In a Review, McGann traces the origins of this false belief back to comparative 19th-century neuroanatomical studies by Broca. A modern look at the human olfactory bulb shows that it is rather large compared with those of rats and mice, which are presumed to possess a superior sense of smell. In fact, the number of olfactory bulb neurons across 24 mammalian species is comparatively similar, with humans in the middle of the pack, and our sense of smell is similar to that of other mammals.
Even if humans doesn’t have such a great sense of smell like the dogs but is better than various mammals out there.
The human olfactory bulb is actually quite large in absolute terms and contains a similar number of neurons to that of other mammals. Moreover, humans have excellent olfactory abilities. We can detect and discriminate an extraordinary range of odors, we are more sensitive than rodents and dogs for some odors.