Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
cam tuc » cam xuc, cam tu, nam thuc
hang di » hang doi, hang vi, hang dien
tuc van » thuc van, truc van, tuc va
qua cam » qua cham, qua cac, qua ca
sach ty » sach y, sach tu, xach tay
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet

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

• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach ty) OR (sach thu)) nang xa hoi. hieu qua cam tuc van ((hang di) OR (hanh vi)) cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((sach ty) OR (sach thu)) nang xa hoi. hieu qua cam tuc van ((hang di) or (hanh vi)) cua tre~".
• Adding a wildcard symbol may retrieve word variants: toc ((sach ty) OR (sach thu)) nang xa hoi. hieu qua cam tuc van ((hang di) or (hanh vi)) cua tre*.