Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hanh lai » hanh lam, hanh tai, thanh lap
cham duc » cham soc, pham duy, phan duc
thu sach » tu sach, thuat sach, thuoc sach
lai hoi » dai hoi, lai hoa, lai roi
mai hoi » mai khoi, dai hoi, mai doi
sach ty » sach y, sach tu, sach thu
va hanh » van hanh, va thanh, va danh
ty nang » ky nang, ty xang, ty hang
lai cua » dai cua, hai cua, lai chau
hieu va » lieu va, hieu qua

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ty nang ((mai hoi) or (lai hoi)). hieu va ((cham duc) OR (pham duc)) va hanh lai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty nang ((mai hoi) OR (lai hoi)). hieu va ((cham duc) OR (pham duc)) va hanh lai cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ty nang ((mai hoi) or (lai hoi)). hieu va ((cham duc) OR (pham duc)) va hanh lai cua triet".
• Adding a wildcard symbol may retrieve word variants: thu sach ty nang ((mai hoi) or (lai hoi)). hieu va ((cham duc) OR (pham duc)) va hanh lai cua triet*.