Perhaps you should try some spelling variations:
nhan luc » nang luc
va triet » va thiet, va trien, ve triet
ban hanh » ban hang
hieu cua » hieu qua, dieu cua, bieu cua
luc ban » duc ban, cuc ban, luc bat
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hieu ca » hieu cac, hieu va, hieu xa
nang xa » nang x, lang xa, nang ma
su viet » so viet

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 ky nang xa hoi. ((hieu ca) OR (hieu cua)) nhan luc ban hanh vi ((va triet) or (su viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. ((hieu ca) OR (hieu cua)) nhan luc ban hanh vi ((va triet) OR (su viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang xa hoi. ((hieu ca) OR (hieu cua)) nhan luc ban hanh vi ((va triet) or (su viet))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. ((hieu ca) OR (hieu cua)) nhan luc ban hanh vi ((va triet) or (su viet))*.