The General Department of Taxation says that at the website for foreign suppliers (https://etaxvn.gdt.gov.vn) posted documents guiding how to make tax registration, tax declaration and payment and search of tax dossiers (in English and Vietnamese).
In addition, there are email and hotline for providing online support for foreign suppliers when they need reply to issues relating to tax registration, tax declaration and payment.
Now, this website officially runs and some foreign suppliers have made tax registration successfully.