If sulphuric acid barely evaporates, why we can smell it?
There are at least two plausible explanations for why an odorless compound with very low vapor pressure could nevertheless generate an odor:

Sulfuric acid is highly reactive.  If you are pouring or dispensing sulfuric acid, you are probably generating some mist. This is a concern in industrial settings where sulfuric acid is used:

https://www.cdc.gov/niosh/docs/81-123/pdfs/0577.pdf

Thus, even if the sulfuric acid itself has neither a significant vapor pressure nor an odor, as the mist enters your nose it could react with substances in your nasal passages to create compounds that have an odor.  Some studies have reported the perception of odor from sulfuric acid mists:
https://www.epa.gov/sites/production/files/2014-09/documents/sulfuric_acid_interim_dec_2008_v1.pdf

And even without misting, particulates in the air, as they fall into an open container of sulfuric acid, could react with sulfuric acid to generate compounds that create a smell.  This effect is seen with metals -- the metallic "smell" is not from the metals themselves (which have an extremely small vapor pressure at room temperature), but from reaction products of the metals:

Why can we smell copper?