Perhaps you should try some spelling variations:
thiet tach » chiet tach, thien hach, thuat tach
hanh trinh » canh tranh, hanh chinh
hoc thiet » hoc thieu, hoc thuyet, hoc hien
cua phong » cua phuong, cuu phong, chau phong
cua khong » hua khong, cua phuong, cua thuong
cong dan » cong san, cong tan, huong dan
dan than » dan chan, ban than, van than
than man » than ma, thanh san, tran manh

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thiet tach - hanh trinh ((cua phong) OR (cua khong)) cong dan than man~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thiet tach - hanh trinh ((cua phong) OR (cua khong)) cong dan than man".
• Adding a wildcard symbol may retrieve word variants: hoc thiet tach - hanh trinh ((cua phong) OR (cua khong)) cong dan than man*.