Perhaps you should try some spelling variations:
thanh trung » thanh tung
thiet tach » chiet tach, thien hach, thuat tach
trung gian » truong giang, truong giao, trong giang
cong thanh » dong thanh, cong trinh, truong thanh
hoc thiet » hoc thieu, hoc thuyet, hoc hien
cong tan » cong tac, cong san, cong ty
toan cau » toan cao, toan tap, toan tai
toan ban » van ban

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 - thanh trung gian trong ((cong thanh) OR (cong tan)) ((toan cau) or (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet tach - thanh trung gian trong ((cong thanh) OR (cong tan)) ((toan cau) OR (toan ban)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thiet tach - thanh trung gian trong ((cong thanh) OR (cong tan)) ((toan cau) or (toan ban))".
• Adding a wildcard symbol may retrieve word variants: hoc thiet tach - thanh trung gian trong ((cong thanh) OR (cong tan)) ((toan cau) or (toan ban))*.