Perhaps you should try some spelling variations:
chat thuc » thuat thuc, nhan thuc, chat thai
hieu van » hieu va, thien van, lieu va
danh dau » lanh dao, hang dau, danh tu
danh dai » danh di, danh sai, vanh dai
van chat » cao chat
nang xa » nang x, lang xa, nang ma
sach ky » sach y, sach ty, sach kem
thuc va » thuc vat, thuc dan, thuc day
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu ((sach ky) or (sac ky)) nang xa hoi. hieu van chat thuc va ((danh dai) OR (danh dau)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ky) OR (sac ky)) nang xa hoi. hieu van chat thuc va ((danh dai) OR (danh dau)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ky) or (sac ky)) nang xa hoi. hieu van chat thuc va ((danh dai) OR (danh dau)) cua tre".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ky) or (sac ky)) nang xa hoi. hieu van chat thuc va ((danh dai) OR (danh dau)) cua tre*.