Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
thanh ve » hanh ve, thanh va, thanh vien
luc van » luoc van, luu van, duc van
cam luc » cam xuc, cau luc
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua
mai hoi » mai khoi, dai hoi, lai hoi
ty nang » ky nang, ty xang, ty hang
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cao
ma hoi » xa hoi, ma hoa, me hoi

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