The Canaries, who won promotion from the Championship by finishing second last season, have added six players to their roster already during the transfer window but Lambert says he will need more depth to, particularly in defence.
"You never stop looking, that is the nature of the game, but the ones we have brought in have added to the squad, which is strong," he said.
"We will try to bring someone else in, there might be one in the backline that I am looking at, but we will have to wait and see."
He added: "I am delighted with the group which I have assembled. They are not just good players, they are good characters, which is important.
"There will be times when disappointment sets in, but as long as they stick together, we will be fine."