Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
sach tham » sach nha
danh vai » danh sai, danh va, doanh van
sach thi » sach thu, sach tai, sach thieu
vai cua » dai cua, hai cua, lai cua
va danh » va dinh, va dan, va hanh
cao duc » dao duc, cao suc, giao duc
hieu va » lieu va, hieu qua
mai hoi » mai khoi, dai hoi, mai doi
lai hoi » dai hoi, lai hoa, lai roi
va cao » va cac, va co, va dao

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

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