Perhaps you should try some spelling variations:
thong quang » thong quan, thong qua, luong quang
trinh thong » trinh thuong, trinh trong, trinh tong
thien hoat » trien hoat, thien thuat, tien hoa
hieu suat » hieu luat, hieu qua
quang van » quang ban, quan van, quang uan
van thien » van tien, van hien, van chien
luan va » luan van, luat va
va hieu » van hieu, va dieu, va hien
tin » tinh

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

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