Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
lang xa » lang ha, dang xay, lang van
sach ky » sach y, sach ty, sach kem
vai cuu » vai cua
cuu tre » cua tre, cau tren, cau treo
sac ky » cac ky, sai ky
va dan » ca dan, va dau, va dap
va dao » ca dao

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 ky) or (sac ky)) lang xa hoi. hieu van nam thuc ((va dan) OR (va dao)) vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach ky) OR (sac ky)) lang xa hoi. hieu van nam thuc ((va dan) OR (va dao)) vai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((sach ky) or (sac ky)) lang xa hoi. hieu van nam thuc ((va dan) OR (va dao)) vai cuu tre".
• Adding a wildcard symbol may retrieve word variants: toc ((sach ky) or (sac ky)) lang xa hoi. hieu van nam thuc ((va dan) OR (va dao)) vai cuu tre*.