Perhaps you should try some spelling variations:
thanh doi » thanh loi, thanh moi, thanh do
hieu van » hieu va, thien van, hieu ve
xa thanh » va thanh, ha thanh, ta thanh
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
tang ma » mang may, tang van
cac toc » cac toi, cac nuoc, cac thoi
doi cua » dai cua, hoi cua
cua tre » cua te, cuu tre, cua triet
toc xa » tuc xa, toc ta, hoc xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ty ((nang cao) or (tang ma)) hoi. ((hieu van) or (lieu va)) cac toc xa thanh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((nang cao) OR (tang ma)) hoi. ((hieu van) OR (lieu va)) cac toc xa thanh doi cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ty ((nang cao) or (tang ma)) hoi. ((hieu van) or (lieu va)) cac toc xa thanh doi cua tre*.