Can I apply for a visa extension while on a visa exemption with a Vietnamese passport?

@Ashley ****

like I said, it depends on the stamp in your passport. If they gave you visa exempt you can extend. If they gave you visa waiver you cannot. You need to look at your passport and figure out which one you got because a vietnamese passport qualifies for both. If you have any questions you can always ask the immigration office and see if they'll give you an extension.