Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
quoc ban » quoc bao, quoc lan, quoc quan
sach ty » sach tu, sach thu, xach tay
luc loi » duc loi, luc moi, luc doi
hieu ve » hieu va, hieu van
xuc ban » duc ban, cuc ban, xuat ban
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: so ((sach ty) OR (sach y)) nang luc loi. hieu ve cam ((xuc ban) or (quoc ban)) thanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so ((sach ty) OR (sach y)) nang luc loi. hieu ve cam ((xuc ban) OR (quoc ban)) thanh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so ((sach ty) OR (sach y)) nang luc loi. hieu ve cam ((xuc ban) or (quoc ban)) thanh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: so ((sach ty) OR (sach y)) nang luc loi. hieu ve cam ((xuc ban) or (quoc ban)) thanh dai cua tre*.