Forest go to Falmer stadium on Sunday.
Nuno said: "We are playing good and doing a lot of things well but we're not getting anything from the games, so the only way to get more points is to try to sustain the level of performances.
"I know they're a good team and how hard it is to play in Europe and have the Premier League either side.
"We are talking about a very good opponent with very good players and a very good manager, so we expect a very tough game."