Despite five wins from their last six matches in all competitions, Silva believes that City continue to have areas that they need to work on.
"I think there is still room for improvement," the Spaniard told the Daily Star.
"Things are heading in the right direction but I think we maybe need to have a tighter unit.
"But once that is done, I think we will be a very good team and tough to beat."
City are back in Champions League action on Tuesday when they welcome CSKA Moscow to the Etihad Stadium.