The Canaries, who gained successive promotions to make their return to the top flight, are currently tenth in the Premier League table.
"There are one or two areas I think you would look to strengthen, there is no doubt about that, but as I said sometimes it is a lot easier to say that than to go and get them in," Lambert told the Eastern Daily Press.
"It's part of the game with agents. You have to go with it. Sometimes if the phone rings I'll think, 'No', sometimes I'll think, 'Yes' - that is the game. January will be like any other January - mayhem."
Norwich travel to Everton in the Premier League on Saturday.