Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
qua cham » qua cac, va cham, qua cua
sach ty » sach y, sach tu, sach thu
dan dat » dung dat, dong dat, dinh dat
dan dai » dat dai, can dai, dan da
ty nang » ky nang, ty xang, ty hang
qua hai » qua hoat
cua tre » cua te, cuu tre, cua triet
tuc va » thuc va, truc va, tuc xa
x hoi » xa hoi, o hoi, x ho

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 ty nang x hoi. hieu ((qua cham) OR (qua hai)) tuc va ((dan dai) or (dan dat)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty nang x hoi. hieu ((qua cham) OR (qua hai)) tuc va ((dan dai) OR (dan dat)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty nang x hoi. hieu ((qua cham) OR (qua hai)) tuc va ((dan dai) or (dan dat)) cua tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ty nang x hoi. hieu ((qua cham) OR (qua hai)) tuc va ((dan dai) or (dan dat)) cua tre*.