Smoke smaller size ?

Tried scaling my object really small but noticed it wouldn’t shrink past a certain size (non particles). How can I make it smaller ? It’s for someone smoking. Also no idea how to make it spread out over lifetime.

Very small smoke domains / smoke emitters are awful to handle. Scale up your character / model so that you don’t have to scale down the smoke objects. The simulations will be far better and easier then.
Regarding smoke spreading: play around with the dissolve value, the temperature difference and vorticity - which can all be found in the smoke domain settings (right below the smoke simulation type buttons)