Perhaps you should try some spelling variations:
trinh hanh » trinh thanh, trinh han, trinh hinh
nhung cong » dung cong, thong cong, hang cong
trinh anh » trinh thanh, trinh kinh, trinh dinh
ho chiet » ho chieu, hoc thiet, hoa thiet
ho thiet » hoc thiet, hoa thiet, so thiet
cong dan » cong san, cong tan, huong dan
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: ((ho chiet) OR (ho thiet)) tach - hanh ((trinh hanh) or (trinh anh)) nhung cong dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chiet) OR (ho thiet)) tach - hanh ((trinh hanh) OR (trinh anh)) nhung cong dan toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chiet) OR (ho thiet)) tach - hanh ((trinh hanh) or (trinh anh)) nhung cong dan toan cau".
• Adding a wildcard symbol may retrieve word variants: ((ho chiet) OR (ho thiet)) tach - hanh ((trinh hanh) or (trinh anh)) nhung cong dan toan cau*.