Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
hanh tranh » canh tranh, hanh trang, lanh tranh
thanh bac » nhanh bac, thanh bai, thanh san
hoa sinh » cho sinh
cong van » cong vang, cong san, cong tan
song van » hoang van, trong van, duong van
hoi hoa » hoi khoa, hoc hoa, hoi hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoi hoa sinh - ((hanh tranh) or (hanh trinh)) va nhung ((cong van) OR (song van)) thanh bac~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoi hoa sinh - ((hanh tranh) OR (hanh trinh)) va nhung ((cong van) OR (song van)) thanh bac.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoi hoa sinh - ((hanh tranh) or (hanh trinh)) va nhung ((cong van) OR (song van)) thanh bac".
• Adding a wildcard symbol may retrieve word variants: hoi hoa sinh - ((hanh tranh) or (hanh trinh)) va nhung ((cong van) OR (song van)) thanh bac*.