Perhaps you should try some spelling variations:
trung thanh » truong thanh
trung tuan » trung tam, tran tuan, truong thanh
nhung cong » dung cong, thong cong, hang cong
hien tach » thien hach, chiet tach, vien bach
cong manh » cong danh, duong manh, cong thanh
toan ban » van ban
toan cao » 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 hien tach - thanh ((trung tuan) OR (trung thanh)) nhung cong manh ((toan ban) OR (toan cao))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien tach - thanh ((trung tuan) OR (trung thanh)) nhung cong manh ((toan ban) or (toan cao))~".
• Adding a wildcard symbol may retrieve word variants: hoc hien tach - thanh ((trung tuan) OR (trung thanh)) nhung cong manh ((toan ban) or (toan cao))*.