Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, hieu lang
thien anh » thien danh, tien anh, thien thanh
tranh va » tranh van, trang va, trinh va
va thong » va thuong, va phuong, he thong
cong dan » cong tan, huong dan, cong dong
cong san » cong tac
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 ((thien anh) or (chieu sang)) - canh tranh va thong ((cong dan) OR (cong san)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thien anh) OR (chieu sang)) - canh tranh va thong ((cong dan) OR (cong san)) toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thien anh) or (chieu sang)) - canh tranh va thong ((cong dan) OR (cong san)) toan cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((thien anh) or (chieu sang)) - canh tranh va thong ((cong dan) OR (cong san)) toan cao*.