Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
cua triet » cua viet, su triet, va triet
hanh vai » hanh vi, hanh va, hanh tai
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
cac hoc » cach hoc, cac hop, bac hoc
hieu ve » hieu va, hieu van
te sach » toc sach
lai hoi » dai hoi, lai hoa, lai roi
mai hoi » mai khoi, dai hoi, mai doi
ky mang » ky nang, ke mang, ky dang
ve cac » va cac, vien cac

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

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