Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
ban hanh » ban hang
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
hoi cua » hoi chuc
cam duc » cam xuc, pham duc, nam duoc
hai cua » thai cua, dai cua, lai cua
sach ky » sac ky, sach y, sach ty
cao duc » dao duc, cao suc, giao duc

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

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