The former RB Leipzig is beginning to find his best form for the Reds.
Mane said: “The real Naby is coming still. We have more to see from him.
“Naby is a big boy so he knows how football can work, and sometimes not. So he is very positive and he knows he can do more.
“I am sure he can do more. We have a lot more to see from him and I am sure we will see it. I know him very well and there is more to come."
Asked if Keita is a player who needs time to adapt, he replied: “I knew him from a long time ago, from the first time he came to Salzburg and he was the same.
“He was not playing for a while and he was really positive and after he was the star of the team. At the beginning at Salzburg it was very tough for him but he never stopped working hard."