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

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