Perhaps you should try some spelling variations:
luoc van » luoc can, luoc va, luot van
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
qua cac » cua cac
luc van » luu van, duc van, luc va
cua tre » cua te, cuu tre, cua triet
anh vi » hanh vi, anh va, anh vu
anh ve » hanh ve, anh va, anh viet

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

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