Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
su triet » su viet, su tien, ve triet
tu cach » tu cac
su sach » so sach, vu sach
hanh va » hang va, hanh vi
ban bo » can bo, ban do, ban co
bo van » vo van, so van, do van
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu cach) or (su sach)) ky nang ((o hoi) or (xa hoi)). hieu van ban bo van hanh va su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (su sach)) ky nang ((o hoi) OR (xa hoi)). hieu van ban bo van hanh va su triet.
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (su sach)) ky nang ((o hoi) or (xa hoi)). hieu van ban bo van hanh va su triet*.