Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
van dau » van dao, phan dau
vai cua » dai cua, lai cua, bai cua
hai cua » thai cua, dai cua, hoi cua
luc va » tuc va, loc va

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

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