Perhaps you should try some spelling variations:
thieu tinh » trieu tinh, chieu tinh, lieu tinh
thien tinh » khien tinh, thien minh, tien tinh
canh trinh » canh tranh, hanh trinh, canh tinh
voi nhung » gioi nhung, va nhung, thi nhung
vi nhung » vai nhung, va nhung, ve nhung
cong san » cong tac
san toan » van toan, dan toan, 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 tinh) or (thien tinh)) - canh trinh ((vi nhung) OR (voi nhung)) cong san toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu tinh) OR (thien tinh)) - canh trinh ((vi nhung) OR (voi nhung)) cong san toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu tinh) or (thien tinh)) - canh trinh ((vi nhung) OR (voi nhung)) cong san toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu tinh) or (thien tinh)) - canh trinh ((vi nhung) OR (voi nhung)) cong san toan cau*.