1.
If a person is sniffing around , they are trying to find out information about something, especially information that someone else does not want known. ( INFORMAL )
But really, what harm could it possibly do to pop down there and just sniff around?...
A couple of plain-clothes men had been sniffing round his apartment.
= nose around
PHRASAL VERB : V P , V P n
2.
If a person or organization is sniffing around someone, they are trying to get them, for example as a lover, employee, or client. ( INFORMAL )
When I had to go away to university, I was convinced that other men would be sniffing round her...
PHRASAL VERB : no passive , V P n