Victory at Blackburn Rovers made it five from six games for Spurs.
"Last week we drew at Newcastle, everyone was disappointed and that means everything, it says a lot about the team," Van der Vaart told the club's website.
"We’re so confident at the moment, we know we can win every game, especially when we play our game and play good football.
"It was important to win at Blackburn. I don’t think we played our best game but we won and that’s what matters. We have five wins and a draw (in the last six matches) and as I said, we have a lot of confidence.
"It’s always tough at Blackburn but we managed to win and we’re up to fifth, so that’s great."