Can only speak about HSBC, they have a Credit Card in a sense. It's a Visa Card, but you need your credit limit backed up by money in another account.
So we have a $4000 limit, say we spend $1000 in BKK, that $1000 then comes directly out of my savings account to pay the Visa, thus having $4000 ready to splash again.
So there is no chance of spending which i haven't got, which suits me fine.
Yep, since it's still all new to Vietnam and there is not any centralize credit history company; banks don't offer credit card in the way most developed countries do.
I had the same problem with ACB and HSBC. Technically it's not a credit card as their policy of freezing the amount given as a limit defies the concept and definition of credit.
As natinnam said, the only way to my knowledge is to block money in order to have a credit card; HSBC, ANZ and other bank will provide you with that type of "credit card".