The Red Devils dropped to fourth in the table after Saturday’s stalemate, with fans left frustrated after witnessing their fourth goalless draw in the Premier League this season.
However, Van Gaal says that while he is disappointed at not being able to break down West Ham, the fans must remain patient with his team.
"I don't understand that they shout 'attack, attack' because we are the dominating team and not West Ham," he told reporters after the game.
"The fans are disappointed, I know that, but so am I and so are the players. They want to score every minute and you cannot.
"I think when we have scored a goal they are very pleased, and they were supportive more than ever I think, so we have to score that goal and we did not do that.
"When you have a lot of ball possession, you have a lot of ball possession to create chances, not to play the ball around and not score."
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"When they don't like the style of play for Manchester United, everybody knows in advance that all the teams of Louis van Gaal plays like that,” he added.
"In Barcelona, or Bayern Munich or AZ we have played like that. But when I meet fans on the streets they are very happy with Manchester United and with me.
"But you have to score, and when you don't you lack points and we are now three points behind Leicester because we don't score.
"Today the team that had to score was Manchester United and not West Ham, but they also could have scored, we could have lost also, and this is the wonderful game of football."