Perhaps you should try some spelling variations:
chat thuc » thuat thuc, nhan thuc, chat thai
thuc day » thuc dan, thuc vat
cua tre » cua te, cuu tre, cua triet
don vai » don vi, den vai, doi vai
hieu va » lieu va, hieu qua
va chat » van chat, va phat, cao chat
tang ma » mang may, tang van
nang xa » nang x, lang xa, nang ma
san ky » sang ky, van ky, dan ky
don va » doan va, dong va, don vi
tu san » thu san, tu ban, tu can

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu san ky ((nang xa) OR (tang ma)) hoi. hieu va chat thuc day ((don vai) OR (don va)) cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu san ky ((nang xa) or (tang ma)) hoi. hieu va chat thuc day ((don vai) OR (don va)) cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu san ky ((nang xa) or (tang ma)) hoi. hieu va chat thuc day ((don vai) OR (don va)) cua tre*.