Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, thien anh, thien danh
hieu manh » chieu xanh, hieu nganh, dieu hanh
hang hang » nang hang, cang thang, hung thang
cua hang » cua dang, cua nhung, cua cong
cong bai » cuong bai, cong hai, cung bai
bai toan » bai tap
toan cau » toan cao, toan ban, toan tap
ca hang » ca chang, va hang, ca tang

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