Perhaps you should try some spelling variations:
thuat nhung » thuat hung, thuat chung, thuat chuong
hanh trinh » canh tranh, hanh chinh
hieu quang » thieu quang, hieu qua, diep quang
hieu quan » hieu qua, lieu quan, thien quan
hong van » hoang van, thong van, phong van
van quan » van ban
quan cu » quan cua, quang cu, quan cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc ((hieu quang) OR (hieu quan)) - hanh trinh ((thuat nhung) or (luat thuong)) hong van quan cu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu quang) OR (hieu quan)) - hanh trinh ((thuat nhung) OR (luat thuong)) hong van quan cu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((hieu quang) OR (hieu quan)) - hanh trinh ((thuat nhung) or (luat thuong)) hong van quan cu".
• Adding a wildcard symbol may retrieve word variants: doc ((hieu quang) OR (hieu quan)) - hanh trinh ((thuat nhung) or (luat thuong)) hong van quan cu*.