Perhaps you should try some spelling variations:
thieu xanh » hieu manh, thien anh, thien danh
chieu xanh » chieu sach, chieu sang, chieu tinh
hanh hang » thanh hang, hang hang, hanh han
hai thong » hai thuong, hai phong, hai trong
hang hai » hoang hai, hang tai, thanh hai
cong tap » cuong tap, cong tac, tong tap
cong tan » cong tac, cong san, cong thanh
toan cau » 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 ((thieu xanh) or (chieu xanh)) - hanh hang hai thong ((cong tap) OR (cong tan)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu xanh) OR (chieu xanh)) - hanh hang hai thong ((cong tap) OR (cong tan)) toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu xanh) or (chieu xanh)) - hanh hang hai thong ((cong tap) OR (cong tan)) toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu xanh) or (chieu xanh)) - hanh hang hai thong ((cong tap) OR (cong tan)) toan cau*.