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 cac » van hac, van cau, van bac
truc va » thuc va, thuc vat, trung va
cua cau » cua cac, cua chu, cua cay
cua tu » cua tuc, cua su, cua cu

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 cac ((duc va) or (truc va)) hanh vi ((cua tu) or (cua cau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang xa hoi. hieu van cac ((duc va) OR (truc va)) hanh vi ((cua tu) OR (cua cau)).
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang xa hoi. hieu van cac ((duc va) or (truc va)) hanh vi ((cua tu) or (cua cau))*.