Perhaps you should try some spelling variations:
toc sach » doc sach, thuoc sach, nuoc sach
hoc sach » hoc sinh, hoc cac, hoc anh
hieu van » hieu va, thien van, lieu va
van cam » van nam, van lam, van cau
cam tuc » cam xuc, cam tu, nam thuc
nang xa » nang x, lang xa, nang ma
tuc va » thuc va, truc va, tuc xa
va dan » ca dan, va dao, va dau
va luu » van luu, vi luu
ta luu » tam luu

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)) ky nang xa hoi. hieu van cam tuc va dan ((va luu) OR (ta luu)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sach)) ky nang xa hoi. hieu van cam tuc va dan ((va luu) OR (ta luu)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) or (hoc sach)) ky nang xa hoi. hieu van cam tuc va dan ((va luu) OR (ta luu)) tre".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (hoc sach)) ky nang xa hoi. hieu van cam tuc va dan ((va luu) OR (ta luu)) tre*.