Perhaps you should try some spelling variations:
trinh thuong » trinh phuong, trinh huong, trinh truong
thuong quang » thong quang, truong quang, phuong quang
quang tan » quang tuan, quang tran, quang toan
hieu soat » hieu suat, hieu hoat, hieu luat
quang ban » quang binh, quang tuan, quang tran
bien soan » bien so
van hieu » cao hieu
ban bien » bang bien, bat bien, bai bien
tan van » tran van, tang van, luan van
tinh » dinh, minh, kinh

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tinh quang tan van hieu soat ) or ( trinh thuong quang ban bien soan ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tinh quang tan van hieu soat ) OR ( trinh thuong quang ban bien soan ))*.