Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu cac » hieu luc, hieu va, hieu van
va triet » va thiet, va trien, ve triet
van hanh » van thanh, ban hanh, van anh
nhan luc » nang luc
su triet » su viet, su tien, ve triet
sach ky » sac ky, sach y, sach ty
hieu ca » hieu cua, hieu va, hieu xa
luc van » luoc van, luu van, duc van
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: thu sach ky nang x hoi. ((hieu ca) OR (hieu cac)) nhan luc van hanh vi ((va triet) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang x hoi. ((hieu ca) OR (hieu cac)) nhan luc van hanh vi ((va triet) OR (su triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang x hoi. ((hieu ca) OR (hieu cac)) nhan luc van hanh vi ((va triet) or (su triet))".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang x hoi. ((hieu ca) OR (hieu cac)) nhan luc van hanh vi ((va triet) or (su triet))*.