Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
sach kem » hanh kem
nang dau » hang dau, xang dau, nang du
tai cua » thai cua, tai cuc, tri cua
hieu ve » hieu va, hieu van
dau hoi » cau hoi, dai hoi, dan hoi
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam
luc va » tuc va, loc va

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

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