Perhaps you should try some spelling variations:
phuong cong » phuong dong, phong cong, phung cong
hieu quang » thieu quang, hieu quan, diep quang
hanh trinh » canh tranh, hanh chinh
chong cong » cong cong, thong cong, cuong cong
trinh cua » tinh cua, trinh luat, trinh quan
dan van » dang van, doan van, dao van
van cau » van dau, van hau, van chat

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: theo ((hieu quang) OR (hieu qua)) - hanh trinh cua ((phuong cong) OR (chong cong)) dan van cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((hieu quang) OR (hieu qua)) - hanh trinh cua ((phuong cong) or (chong cong)) dan van cau~".
• Adding a wildcard symbol may retrieve word variants: theo ((hieu quang) OR (hieu qua)) - hanh trinh cua ((phuong cong) or (chong cong)) dan van cau*.