Perhaps you should try some spelling variations:
cua triet » su triet, va triet
ban hanh » ban hang
cua viet » ca viet, hoa viet, cua vat
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
bac lo » bac bo, bac ho, bac le
lo ban » co ban, lo van, ly ban
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: tu sach ky nang x hoi. ((hieu ve) or (hieu qua)) bac lo ban hanh vi ((cua triet) OR (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang x hoi. ((hieu ve) OR (hieu qua)) bac lo ban hanh vi ((cua triet) OR (cua viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang x hoi. ((hieu ve) or (hieu qua)) bac lo ban hanh vi ((cua triet) OR (cua viet))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang x hoi. ((hieu ve) or (hieu qua)) bac lo ban hanh vi ((cua triet) OR (cua viet))*.