I dont speak vietnamese (sp?) but I think the problem is with these 2 variables:
ChuDe
NoiDung
Probably what is happening is that yahoo either A)Cant interpet vietnamese and is flagging it as spam or B)It is translating your message and flagging it as spam.
In either case there is nothing any of us can do other then to tell you to alter your message since we obviously dont control Yahoo's spam filters.
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