City have scored just 61 goals with three games to go this season, which is considerably fewer than the 93 times they netted on their way to winning the Premier League last year.
The Manchester outfit are thought to be targeting new additions to their front line before next term, but Mancini insists that all of his focus is on the current campaign.
"We can't know which player can score 25 goals next year. If we knew that we would be magicians," Mancini told Sky Sports News.
"We have good players and were unlucky this season. Now it is important we win the FA Cup and then try to improve our team."