Perhaps you should try some spelling variations:
nhieu tang » chieu sang, hieu lang, nhiet nang
chieu sach » chinh sach, chiet tach, chieu sang
trung tuan » trung thanh, trung tam, truong thanh
tran tuan » tran xuan, tran quang, tran thanh
dung tong » dung trong, dung thong, dung cong
tong tap » tuong tac, trong tan, cong tac
tap doan » tap quan
doan cau » toan cau, doan dau, doan cap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((nhieu tang) or (chieu sach)) - manh ((trung tuan) OR (tran tuan)) dung tong tap doan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((nhieu tang) OR (chieu sach)) - manh ((trung tuan) OR (tran tuan)) dung tong tap doan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((nhieu tang) or (chieu sach)) - manh ((trung tuan) OR (tran tuan)) dung tong tap doan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((nhieu tang) or (chieu sach)) - manh ((trung tuan) OR (tran tuan)) dung tong tap doan cau*.