有外国人试过在中国申请越南落地签吗？Foreign

有外国人试过在中国申请越南落地签吗？
看到 GOOGLE / BAIDU上有人(指外国人, I mean foreign citizen)是在中国网上申请越南落地签，价格也便宜又方便。
望高人(有经验的外国人)指点！谢谢！！！
Has anyone experienced problem of get an online approval letter (incorrectly called Visa On Arrival) going into Vietnam from China? I saw lot of information that approval letter on GOOGLE and other websites. can offer any suggestions on obtaining a visa when entering Vietnam other than air? Thanks