SEA Games champion Dao Hong Son made the most remarkable victories with all three wins by submission in the men's U56kg.
"It was a hard-working day. But the result was so sweet, with three submission wins. Thank you for watching and encouraging me," Son posted on his Facebook page.
Earlier, world champion Phung Thi Hue secured gold in the women's U45kg category.
Hoang Thi Nhat Que won the women's U70kg class and Pham Tri Dung topped the men's U69kg pool.
The Vietnamese team also brought home one silver by Pham Le Hoang Linh in the men's U85kg and 11 bronze medals.
On the last day, athletes will vie for medals in the men's and women's team events.