Perhaps you should try some spelling variations:
chat triet » chet triet, chat thien, cua triet
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
van chu » van chi, van phu, van cau
chu duc » thu duc, chua duoc, cuu duoc
va hanh » van hanh, va thanh, va danh
hanh va » hang va, hanh vi
o hoi » co hoi, o hoc, o hoa
o hai » co hai, so hai, o lai
phat » phan, pham, phap

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 ky nang ((o hoi) or (o hai)). hieu van chu duc va hanh va ((chat triet) or (phat trien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ((o hoi) OR (o hai)). hieu van chu duc va hanh va ((chat triet) OR (phat trien)).
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ((o hoi) or (o hai)). hieu van chu duc va hanh va ((chat triet) or (phat trien))*.