Perhaps you should try some spelling variations:
trien hoat » tien hoa
trinh han » trinh quan
hieu soat » hieu suat, hieu hoat, hieu luat
van trien » van tien, va trien, van tren
tang van » dang van, hoang van, trong van
van hieu » cao hieu
dung nam » dong nam, dung lam, sung nam
nam van » nam dan, nam va, pham van

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( ((trinh han) or (tinh quang)) tang van hieu soat ) or ( tin dung nam van trien hoat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( ((trinh han) OR (tinh quang)) tang van hieu soat ) OR ( tin dung nam van trien hoat )).
• Adding a wildcard symbol may retrieve word variants: (( ((trinh han) or (tinh quang)) tang van hieu soat ) or ( tin dung nam van trien hoat ))*.