Perhaps you should try some spelling variations:
thien hoat » trien hoat, thien thuat, tien hoa
tinh dung » trinh dung, tin dung, tinh quang
dung land » dung luan, dung lam, dung san
hieu suat » hieu luat, hieu qua
luan dang » luan nang, luan danh, luan dong
land van » lang van, lan van, luan van
tin quan » tinh quang, trinh quan, lien quan
dieu hat » dieu hanh, dieu khac, dieu can

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tinh dung land van ((thien hoat) or (hieu suat)) ) or ( tin quan luan dang dieu hat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tinh dung land van ((thien hoat) OR (hieu suat)) ) OR ( tin quan luan dang dieu hat )).
• Adding a wildcard symbol may retrieve word variants: (( tinh dung land van ((thien hoat) or (hieu suat)) ) or ( tin quan luan dang dieu hat ))*.