Van Gaal's team have posted unconvincing victories over Ghana and Wales respectively in the last week as they gear up for their tournament opener against the country who beat them in the 2010 World Cup final, Spain, on June 13.
However, the outgoing coach - who will take over at Manchester United following the World Cup - believes the Netherlands have what it takes to have an impact in Brazil.
"We're not going to South America to just be involved, we want to perform there and my feelings about it are good," Van Gaal said on Thursday.
"The atmosphere is good, we have grown closer together during the training camp.
"Of course we are in a tough group, but I will not assume that have to go home after a few games.
"All the so-called top countries are struggling (in friendlies), so we are really not as bad as many experts think."
After facing Spain, the Netherlands will then meet Australia and Chile in Group B.
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