Perhaps you should try some spelling variations:
cach thuc » anh thuc, cac thu
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
sach thu » sach thue, sach thieu, sach tham
lang xa » lang ha, dang xay, lang van
va dinh » van dinh, va kinh, vu dinh
va tinh » may tinh
cua tre » cua te, cuu tre, cua triet
va cua » va chua, via cua, ca cua

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

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