Perhaps you should try some spelling variations:
thanh trung » thanh tung
nhung cong » dung cong, thong cong, hang cong
thieu qua » thieu cua, thieu quang, thien quan
trung cam » trung tam, trung cap, trung nam
cam nhung » cam hung, nam nhung, tham nhung
cong dan » cong san, cong tan, huong dan
toan cau » toan ban, toan tap, toan tai
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 ((hieu qua) OR (thieu qua)) - thanh trung cam nhung cong dan ((toan cau) OR (toan cao))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu qua) or (thieu qua)) - thanh trung cam nhung cong dan ((toan cau) OR (toan cao))~".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu qua) or (thieu qua)) - thanh trung cam nhung cong dan ((toan cau) OR (toan cao))*.