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