Perhaps you should try some spelling variations:
cach thuc » anh thuc, cac thu
van cach » va cach, van canh, vat cach
day danh » day manh, dai danh, dao danh
day dinh » dao dinh, dang dinh, doan dinh
hieu van » hieu va, thien van, lieu va
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
di cua » dai cua, doi cua, de cua

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 (cac ky)) nang xa hoi. hieu van cach thuc ((day dinh) or (day danh)) di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ky) OR (cac ky)) nang xa hoi. hieu van cach thuc ((day dinh) OR (day danh)) di cua tre.
• Adding a wildcard symbol may retrieve word variants: thu ((sach ky) or (cac ky)) nang xa hoi. hieu van cach thuc ((day dinh) or (day danh)) di cua tre*.