Perhaps you should try some spelling variations:
chieu sang » chieu sach, hieu lang, nhieu tang
chieu xanh » chieu sach, chieu tinh, hieu manh
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 van » cong vang, cong san, song van
van toan » van tuan, van tan, van thanh
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 ((chieu sang) or (chieu xanh)) - hanh ((trung tuan) OR (tran tuan)) nhung cong van toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sang) OR (chieu xanh)) - hanh ((trung tuan) OR (tran tuan)) nhung cong van toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sang) or (chieu xanh)) - hanh ((trung tuan) OR (tran tuan)) nhung cong van toan cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) or (chieu xanh)) - hanh ((trung tuan) OR (tran tuan)) nhung cong van toan cao*.