Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
dinh tai » dinh toai, dinh tri, dinh thi
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
cam tuc » cam xuc, cam tu, nam thuc
va dinh » van dinh, va kinh, va tinh
tai cua » thai cua, tai cuc, tri cua
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cao
tuc va » thuc va, truc va, tuc xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) or (toc sach)) ky lang xa hoi. lieu va cam tuc va dinh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky lang xa hoi. lieu va cam tuc va dinh tai cua tre.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) ky lang xa hoi. lieu va cam tuc va dinh tai cua tre*.