Wilson, whose side have slipped out of the automatic promotion places in recent weeks after taking only two points from their last four league matches, said the 24-year-old Scot is aware his performances have fallen below par.
"We need the lads to have a clear mindset of what they are trying to do when they get on the ball because we aren't taking games by the scruff of the neck and killing teams off," Wilson said after the weekend draw at Notts County.
"Kevin has the ability to score goals and has had chances of late, but he keeps getting caught between two stones and hasn't produced an end product.
"For me Kevin needs to do a lot more and the lad himself knows he is capable of much better."
The Blades head to Reading in the fourth round of the FA Cup on Saturday and after Tuesday night's game at Bury was postponed, must wait until the home game with Coventry on February 1 to try and secure their first league win since Boxing Day.