Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
van hanh » van thanh, ban hanh, van anh
sach ky » sac ky, sach y, sach ty
hieu va » hieu qua
cao duc » dao duc, cao suc, giao duc
duc van » duc va, duc tan, duc manh
co cua » con cua, cong cua, cuoi cua
x hoi » xa hoi, o hoi, x ho

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

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