Perhaps you should try some spelling variations:
thien danh » thien anh, thien dang, thien thanh
chieu xanh » chieu sach, chieu sang, chieu tinh
thong cong » trong cong, tong cong, thong thong
khoan va » doan va, khoa ma, nhan va
cong san » cong tac
san toan » van toan, dan toan, manh toan
toan cau » toan cao, toan ban, toan tap
khoa va » khoa ma, hoa va, khoa ha

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 danh) or (chieu xanh)) - doanh ((khoa va) OR (khoan va)) thong cong san toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thien danh) OR (chieu xanh)) - doanh ((khoa va) OR (khoan va)) thong cong san toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thien danh) or (chieu xanh)) - doanh ((khoa va) OR (khoan va)) thong cong san toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((thien danh) or (chieu xanh)) - doanh ((khoa va) OR (khoan va)) thong cong san toan cau*.