Woods converted a 13th-minute penalty to set Doncaster on their way to a two-goal lead over the weekend at local rivals Scunthorpe, who fought back to salvage a point with a late penalty.
Woods said: "We want to be pushing on and kicking on up the table and you're not going to do that unless you defend better.
"To play well and not take the win has been the story last season and a couple of games this season. It's not acceptable and we've got to finish teams off.
"It's been a set piece again. It's something we've been working on. You can't fault the gaffer for that. He can't do any more, it's just individuals not marking their man or somebody wanting it a bit more and getting their head on the ball.
"It's something we need to do better. We go a goal down and you see the teams just defend the rest of the game - it's so hard to break them down. We've got to get that into our game more."