Perhaps you should try some spelling variations:
thien danh » thien anh, thien dang, thien thanh
chieu xanh » chieu sach, chieu sang, chieu tinh
nhung cong » dung cong, thong cong, hang cong
hanh hang » thanh hang, hang hang, hanh han
manh toan » thanh toan, anh tuan, tinh toan
dan toan » van toan, dan than, xuan toan

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