> For the complete documentation index, see [llms.txt](https://help.myacc.vn/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.myacc.vn/uu-dai-hau-mai/uu-da-cho-khach-hang-cu.md).

# Ưu đã cho khách hàng cũ