Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
chieu xanh » chieu sang, chieu tinh, hieu manh
nhung cong » dung cong, thong cong, hang cong
trung cam » trung tam, trung nam, trung ca
trung cap » truong cao, trung tam
cong van » cong vang, cong san, song van
van han » van hanh, van phan, van nhan
han tai » hang tai, nhan tai, van tai

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 sach) or (chieu xanh)) - hanh ((trung cam) OR (trung cap)) nhung cong van han tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sach) OR (chieu xanh)) - hanh ((trung cam) OR (trung cap)) nhung cong van han tai.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sach) or (chieu xanh)) - hanh ((trung cam) OR (trung cap)) nhung cong van han tai".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sach) or (chieu xanh)) - hanh ((trung cam) OR (trung cap)) nhung cong van han tai*.