United occupy 34 points behind Liverpool in fifth position and are engaged in a battle to secure Champions League football for next season.
Manager Ole Gunnar Solskjaer, however, presides over good form, and with the recent results proving impressive and the signing of Bruno Fernandes in January, Scholes is confident that his former team will once again be able to challenge at the top.
“There is a big gap to be filled, there is no doubt about it,” Scholes told BBC Radio Five Live.
“The difference in points is ridiculous and the quality of Man City is obviously there for everyone.
“I really don’t think they are a million miles away. I know we talked about four or five players, but I think it’s two or three now.
“I think you’re looking for a center forward, a really classy goalscorer and maybe a half center to play next to [Harry] Maguire.
“Look, I think [Victor] Lindelof did well but I just think that Maguire with his lack of rhythm sometimes (can get caught).
“If he has a really dominant half-center next to him like a Rio Ferdinand or Jaap Stam who intimidates the center forward, I think it would be of great help to the team. ”
United would narrow the gap to 31 points with a home win against Bournemouth on Saturday, with Liverpool hosting Aston Villa on Sunday.