Perhaps you should try some spelling variations:
ban hanh » ban hang
te sach » toc sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
cac duc » cac du, cac dac, cac nuoc
cao duc » dao duc, cao suc, giao duc
cua cu » cua chu, cua cau, cua co
cua su » qua su

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky nang xa hoi. hieu ve ((cac duc) or (cao duc)) ban hanh vi ((cua cu) OR (cua su))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang xa hoi. hieu ve ((cac duc) OR (cao duc)) ban hanh vi ((cua cu) OR (cua su)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang xa hoi. hieu ve ((cac duc) or (cao duc)) ban hanh vi ((cua cu) OR (cua su))".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang xa hoi. hieu ve ((cac duc) or (cao duc)) ban hanh vi ((cua cu) OR (cua su))*.