Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
cua triet » cua viet, su triet, va triet
lieu van » lieu va, hieu van, sieu van
van hanh » van thanh, ban hanh, van anh
tham duc » pham duc, tham du, than duc
van tham » van thanh, van tuan, van chat
thu sach » tu sach, thuat sach, thu hoach
duc van » duc va, duc tan, duc manh
hanh di » hanh vi, hanh de, hang di
di cua » dai cua, doi cua, de cua
o hoi » co hoi, o hoc, o hai
x hoi » xa hoi, x ho, 5 hoi

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) or (thuoc sach)) ky nang ((x hoi) OR (o hoi)). lieu van tham duc van hanh di cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (thuoc sach)) ky nang ((x hoi) OR (o hoi)). lieu van tham duc van hanh di cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) or (thuoc sach)) ky nang ((x hoi) OR (o hoi)). lieu van tham duc van hanh di cua triet".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (thuoc sach)) ky nang ((x hoi) OR (o hoi)). lieu van tham duc van hanh di cua triet*.