Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, thien anh, thien danh
nhung tung » nhung tuong, nhung dung, nhung vung
hieu manh » chieu xanh, hieu nganh, dieu hanh
trang cua » tranh cua, tang cua, trung cua
tung dan » dung dan, huong dan, trung dai
dan toan » van toan, dan than, manh toan
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 (hieu manh)) - hanh ((trang cua) or (trung tam)) nhung tung dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu xanh) OR (hieu manh)) - hanh ((trang cua) OR (trung tam)) nhung tung dan toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu xanh) OR (hieu manh)) - hanh ((trang cua) or (trung tam)) nhung tung dan toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu xanh) OR (hieu manh)) - hanh ((trang cua) or (trung tam)) nhung tung dan toan cau*.