Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh tai, hanh van
su sach » so sach, vu sach
sach le » cach le, sach de, sach lo
le xang » le tang, le dang, le quang
xang xa » lang xa, mang xa, ang xa
hanh va » hang va, hanh vi
va cao » va cac, va co, va dao
thiet » thieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach le xang xa hoi. hieu ((va cao) or (ca dao)) duc va ((hanh vai) OR (hanh va)) va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach le xang xa hoi. hieu ((va cao) OR (ca dao)) duc va ((hanh vai) OR (hanh va)) va thiet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach le xang xa hoi. hieu ((va cao) or (ca dao)) duc va ((hanh vai) OR (hanh va)) va thiet".
• Adding a wildcard symbol may retrieve word variants: su sach le xang xa hoi. hieu ((va cao) or (ca dao)) duc va ((hanh vai) OR (hanh va)) va thiet*.