Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
viet tach » viet sach, viet tech, viet thanh
tranh cua » doanh cua, manh cua
cua nhung » va nhung
cong tinh » cong trinh, cong vinh, long tinh
doi viet » dai viet, hoi viet, oi viet
chai tu » choi tu, chay tu, chay tui
chi tu » choi tu, thi tu, chi su
cai tu » tai tu, mai tu

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: doi viet tach - canh tranh cua nhung cong tinh ((((chi tu) OR (chai tu))) OR (cai tu))~.
• Adding a wildcard symbol may retrieve word variants: doi viet tach - canh tranh cua nhung cong tinh ((((chi tu) or (chai tu))) or (cai tu))*.