United displayed clinical form in front of goal as Wayne Rooney, Juan Mata and Robin van Persie were on target to ensure a sixth straight triumph by a comfortable margin over their fierce rivals on Sunday.
But Van Gaal's team were indebted to a string of fine saves from David de Gea in between their scoring exploits and some wayward work in possession from the hosts served to keep Liverpool in the hunt at Old Trafford.
"I think the most important match is the next match and we have to see match by match," Van Gaal said at his post-match press conference.
"Six wins in a row is fantastic but we have to improve our playing style still and I'm saying that nearly every week.
"Only after the matches against Queens Park Rangers and Hull City, I’ve said 'okay' - that was dominating the game for 90 minutes.
"We could have dominated the game also for 90 minutes today but we didn't do that because we gave unnecessary balls away and we had a lot of time and a lot of space, in the second half especially.
"You can kill the game must more easy so we have to improve, but we are very pleased because we know what it is to win against Liverpool. Everybody is happy."
De Gea took much of the post-match plaudits but Van Gaal refused to single out individuals within a team performance that pleased him overall.
"I think the team has done very well and De Gea has contributed to a big part of that," the Dutchman added.
"We are doing it like a team and a team is winning - not one player is winning.
"I can mention also other players whose influence was high but the press wants always one or two.
"I have seen more than three players who were very good today. So I want to mention the team instead of an individual player. That is my philosophy."
