Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
chieu sach » chinh sach, chiet tach, chieu sang
trung tuan » trung thanh, trung tam, truong thanh
nhung cong » dung cong, thong cong, hang cong
tran tuan » tran xuan, tran quang, tran thanh
cong tan » cong tac, cong san, cong thanh
tan toan » tan tran, tap toan, van toan
toan cau » toan cao, toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu quang) or (chieu sach)) - hanh ((trung tuan) or (tran tuan)) nhung cong tan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu quang) OR (chieu sach)) - hanh ((trung tuan) OR (tran tuan)) nhung cong tan toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu quang) or (chieu sach)) - hanh ((trung tuan) or (tran tuan)) nhung cong tan toan cau*.