Perhaps you should try some spelling variations:
ban hanh » ban hang
va trien » va truyen, va thiet, va tuyen
su triet » su viet, su tien, ve triet
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu va » hieu qua
luc ban » duc ban, cuc ban, luc bat

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