Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hang tai » hang va, dung tai
hanh tai » thanh tai, han tai, hinh tai
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cuu tre, cua triet
vu cham » va cham, vu kham, tu cham
hieu vu » hieu va, hieu ve, hieu su
nang xa » nang x, lang xa, nang ma
lo van » le van, vo van, do van
so van » su van, vo van

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 vu cham ((lo van) or (so van)) ((hanh tai) OR (hang tai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang xa hoi. hieu vu cham ((lo van) OR (so van)) ((hanh tai) OR (hang tai)) cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang xa hoi. hieu vu cham ((lo van) or (so van)) ((hanh tai) OR (hang tai)) cua tre*".