Perhaps you should try some spelling variations:
trinh hang » trinh han, tranh hang, trinh hanh
hang hang » nang hang, cang thang, hung thang
hieu soat » hieu suat, hieu luat, kiem soat
hieu hoat » hieu hoa, thien hoat, hieu luat
dung lang » dung dang, dung nang, dung land
kien soat » kiem soat, bien soan, kien hoa
lang van » dang van, tang van, hoang van
van kien » van tien, van hien, van chien

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

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