In the four.0 era, Viettel's social obligation is standing aspect by aspect with several models and companies to create alternatives to produce a breakthrough technology, partaking for a prosperous Vietnam.2011: Nhà cung c?p d?ch v? vi?n thông t?t nh?t th? gi?i t?i các th? tr??ng ?ang phát tri?n – WCA.H? tr? khách hàng Câu h?i th??ng g?p M