The German champions have made a slow start to the Bundesliga and Van Gaal said they were still feeling the effects of a short preparation for the season, a result of the World Cup in which a number of their players played a prominent role.
"It's always difficult when a team has a lot of players at the World Cup and they cannot enjoy a good preparation," the volatile Dutchman told reporters. "This year was a very extreme case.
"So we had to do our preparations by playing in the Bundesliga, the German Cup and the Champions League, and that is naturally a bad thing."
Van Gaal, who led Bayern's Bundesliga celebrations with an unforgettable speech from the balcony of Munich's town hall, said he hoped Tuesday's Champions League match at Swiss champions FC Basel could provide a similar springboard.
"If we win really well, that could be a turning point, the same thing happened with the Juventus game last season," said Van Gaal, whose team beat AS Roma 2-0 in their opening group match two weeks ago.
He added: "In five of our Bundesliga matches, we have played well, we have always been the better team and we created more chances, but we are not finding it easy to score goals."
