Profit earned in Vietnam does not become remittable simply because it was earned. A set of conditions has to be satisfied first, the figures have to reconcile across several documents prepared by different people at different times, and the transfer itself has to leave through the right account.
A foreign-invested enterprise in Vietnam runs its investment capital through a dedicated account, held separately from the account it uses for trading day to day. Which transaction belongs in which account is not a matter of preference. The distinction governs whether money can lawfully enter or leave, and a payment made through the wrong one is often discovered late, by an auditor, when unwinding it is expensive.
A loan from a parent company to its Vietnamese subsidiary is not simply an intercompany balance. Depending on its terms, and on what happens to it afterwards, it may fall within the State Bank’s registration regime, with obligations that begin running from events rather than from dates in a diary.
When an investor sells its stake, when a project reaches its end, or when a company is wound up, the proceeds have to leave by a defined route. The route depends on what is being transferred and to whom, and the choice is made long before anyone reaches the payment.