查收 is the standard polite formula in Chinese emails and letters, almost always paired with 请 ('please') as 请查收 - the rough equivalent of 'please find attached'. Using it without 请 sounds curt; using it in casual speech sounds bureaucratic.
usage
查 = 'check', 收 = 'receive'. So literally: 'check (it) and receive (it)'. The receiver is asked both to verify the contents and to confirm acceptance.
