The Red Devils scored two of their five goals against Bayer Leverkusen from dead-ball situations, in addition to Patrice Evra's headed goal from a Wayne Rooney corner during their 2-2 draw with Cardiff City last weekend.
Evans scored United's third goal against the Germans in midweek and he believes that their potency from such positions has made a huge impact.
"I think our set pieces, especially the deliveries, have been fantastic," he told MUTV. "It makes a big difference. I also think the lads are attacking the ball well.
"Although my goal was a tap-in, Pat got his head to it first and he scored at the weekend too. He has got great spring for the size of him and got the first touch. Wayne Rooney volleyed, the keeper spilled it and it was good getting to the ball first. It shows our determination to do that".
Manchester United visit Tottenham Hotspur in the Premier League on Sunday.