Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
nam thuc » nam thuoc, am thuc, nam thu
sach thu » sach thue, sach thieu, sach tham
va thanh » gia thanh, va tinh, le thanh
cua tre » cua te, cuu tre, cua triet
sach ty » sach y, sach tu, xach tay
hieu va » lieu va, hieu qua
lang xa » lang ha, dang xay, lang van
va cua » va chua, via cua, ca cua
va nam » van nam, ha nam, va nay

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc ((sach ty) or (sach thu)) lang xa hoi. hieu va nam thuc ((va thanh) or (ban thanh)) va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach ty) OR (sach thu)) lang xa hoi. hieu va nam thuc ((va thanh) OR (ban thanh)) va cua tre.
• Adding a wildcard symbol may retrieve word variants: toc ((sach ty) or (sach thu)) lang xa hoi. hieu va nam thuc ((va thanh) or (ban thanh)) va cua tre*.