Perhaps you should try some spelling variations:
thanh trung » thanh tung
thiet tach » chiet tach, thien hach, thuat tach
trung cau » trung cap, trung ca, trung can
ho thiet » hoc thiet, hoa thiet, so thiet
cong dan » cong tan, huong dan, cong dong
cong san » cong tac
toan cau » toan ban, toan tap, toan tai
toan cao » toan ban, toan tap
cau hoa » cau hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho thiet tach - thanh trung cau hoa ((cong dan) or (cong san)) ((toan cau) or (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho thiet tach - thanh trung cau hoa ((cong dan) OR (cong san)) ((toan cau) OR (toan cao)).
• Adding a wildcard symbol may retrieve word variants: ho thiet tach - thanh trung cau hoa ((cong dan) or (cong san)) ((toan cau) or (toan cao))*.