Perhaps you should try some spelling variations:
thuc dao » thuc dan, chuc dao, thuc cao
thuc day » thuc dan, thuc vat
vai cuu » vai cua
dan vai » dan va, dan tai, dan vat
hieu va » lieu va, hieu qua
lang xa » lang ha, dang xay, lang van
cuu tre » cua tre, cau tren, cau treo
va nam » van nam, ha nam, va nay
sai ky » sac ky

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

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