Perhaps you should try some spelling variations:
trung tuan » trung thanh, trung tam, tran tuan
nhung cong » dung cong, thong cong, hang cong
theo cau » theo chu, theo cap, theo dau
cau sach » cao sach, hau sach, rau sach
dung cua » dung luan, dung cho
san toan » dan toan, manh toan, xuan toan
van toan » van tuan, van tan, van thanh

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo cau sach - hanh ((dung cua) or (trung tuan)) nhung cong ((san toan) OR (van toan)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo cau sach - hanh ((dung cua) OR (trung tuan)) nhung cong ((san toan) OR (van toan)) cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo cau sach - hanh ((dung cua) or (trung tuan)) nhung cong ((san toan) OR (van toan)) cao".
• Adding a wildcard symbol may retrieve word variants: theo cau sach - hanh ((dung cua) or (trung tuan)) nhung cong ((san toan) OR (van toan)) cao*.