Perhaps you should try some spelling variations:
thanh doi » thanh loi, thanh moi, thanh do
ban thanh » ban hanh, ban hang
cau hoa » cau hoi
doi cua » dai cua, hoi cua
hoa ban » hoa dan, hoa van, hoa han
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach ty, sach kem
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ky) or (sach y)) nang xa hoi. ((hieu ve) or (lieu va)) cau hoa ban thanh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach y)) nang xa hoi. ((hieu ve) OR (lieu va)) cau hoa ban thanh doi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach y)) nang xa hoi. ((hieu ve) or (lieu va)) cau hoa ban thanh doi cua tre*.