Esmee Brugts and Jill Roord both scored twice in the biggest win yet at the tournament, eclipsing Germany's 6-0 thumping of Morocco.
A crowd of 8,215 were treated to a Dutch goal bonanza in Dunedin and having won Group E the 2019 runners-up will almost certainly now avoid Sweden in the next round. Italy or South Africa are probably next.
In the build-up to the Vietnam game Jonker said he did not want to play Sweden, who routed Italy 5-0 at the weekend, but after a rampant Dutch performance he believes his team should not fear anyone.
"From the beginning of our preparations we were quite convinced we can beat every opponent in this tournament," said Jonker.
"Of course it helps if you qualify first when the United States is in your group, you win 7-0 and you make wonderful goals."
The Netherlands went out in the quarter-finals of last summer's Euros, but Jonker said his Dutch team are a different proposition now.
"A year ago we saw all sorts of teams in Europe who were better than us, but we managed to close the gap," he said.
"So I think we can rightfully state that we will be able to win against anybody, but we have to make it happen."
World Cup debutants Vietnam were under pressure from the opening minute and the Dutch chalked up 42 shots on goal over the 90 minutes.
They scored their first four goals against already eliminated Vietnam inside the opening 23 minutes, the pick of which saw Brugts hit the top corner.
Lieke Martens grabbed the first goal with eight minutes played when she lobbed her marker and Vietnamese goalkeeper Thi Kim Thanh Tran.
Forward Katja Snoeijs made it 2-0 three minutes later when she stroked her effort inside the post past the stranded Tran.
After Brugts's superb third, Roord volleyed in a cross for her first goal on 23 minutes.
With half-time approaching, Tran put in a superb save to deny Roord, but midfielder Danielle van de Donk was on hand to slot home the rebound to make it 5-0 at the break.
Tran was replaced in the Vietnam goal by Thi Hang Khong for the second half, while 17-year-old Wieke Kaptein came on to make her third appearance for the Dutch.
Brugts scored again, from outside the area, when she fired into the opposite corner with a fierce strike that gave Khong no chance.
Martens had a goal ruled offside by the VAR before Roord, who had also clattered the woodwork, headed in the seventh goal with seven minutes left.