Perhaps you should try some spelling variations:
nhanh mang » nhanh lang, hanh mang, nhanh quang
hieu quan » hieu qua, lieu quan, thien quan
cong doan » cong hoan, dong doanh, cong san
cong dan » cong san, cong tan, huong dan
ho hieu » ho chieu, hoi hieu, nho hieu
mang va » mang vua, hang va, bang va
va tong » va thong, va tuong, va trong

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho hieu quan - nhanh mang va tong ((cong doan) OR (cong dan)) van ban~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho hieu quan - nhanh mang va tong ((cong doan) OR (cong dan)) van ban*".