Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
quoc ban » quoc bao, quoc lan, quoc quan
cua tre » cua te, cuu tre, cua triet
xuc ban » duc ban, cuc ban, xuat ban
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
ty nang » ky nang, ty xang, ty hang
anh de » hanh de, anh d, anh ve
de cua » le cua, te cua, dieu cua
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: ((tu cac) or (toc sach)) ty nang x hoi. hieu ve cham ((xuc ban) OR (quoc ban)) anh de cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cac) OR (toc sach)) ty nang x hoi. hieu ve cham ((xuc ban) OR (quoc ban)) anh de cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu cac) or (toc sach)) ty nang x hoi. hieu ve cham ((xuc ban) OR (quoc ban)) anh de cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu cac) or (toc sach)) ty nang x hoi. hieu ve cham ((xuc ban) OR (quoc ban)) anh de cua tre*.