Perhaps you should try some spelling variations:
cham truc » cau truc, nham thuc, pham thuc
thu nang » thi nang, thu hang, thu bang
qua cham » qua hai, qua cac, va cham
toc sach » doc sach, thuoc sach, nuoc sach
hoc sach » hoc sinh, hoc cac, hoc anh
nang xa » nang x, lang xa, nang ma
truc va » thuc va, thuc vat, trung va
hang vi » hang va, hanh vi, khang voi
hang di » hang doi, hang dien, hang dich
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sach) OR (hoc sach)) thu nang xa hoi. hieu qua cham truc va ((hang vi) or (hang di)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sach)) thu nang xa hoi. hieu qua cham truc va ((hang vi) OR (hang di)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (hoc sach)) thu nang xa hoi. hieu qua cham truc va ((hang vi) or (hang di)) cua tre".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) OR (hoc sach)) thu nang xa hoi. hieu qua cham truc va ((hang vi) or (hang di)) cua tre*.