Perhaps you should try some spelling variations:
thiet tach » chiet tach, thien hach, thuat tach
hoc thiet » hoc thieu, hoc thuyet, hoc hien
manh hung » anh huong
cua nhung » va nhung
hung cua » huong cua, chung cua, khung cua
cong dan » cong san, huong dan, cong dong
cong tan » cong tac, cong san, cong thanh
toan cau » toan cao, toan ban, toan tap

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet tach - manh hung cua nhung ((cong dan) OR (cong tan)) ((toan cau) OR (van ban))~.
• Adding a wildcard symbol may retrieve word variants: hoc thiet tach - manh hung cua nhung ((cong dan) or (cong tan)) ((toan cau) or (van ban))*.