Perhaps you should try some spelling variations:
danh viet » anh viet, ninh viet, nang viet
tham thuc » nham thuc, pham thuc, tam thuc
doc sach » hoc sach, toc sach, nuoc sach
han danh » van danh, phan dang, nhan dang
viet cua » viec cua, viet ca, viet qua
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc sach ky nang xa hoi. hieu va ((tham thuc) or (am thuc)) han danh viet cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach ky nang xa hoi. hieu va ((tham thuc) OR (am thuc)) han danh viet cua tre.
• Adding a wildcard symbol may retrieve word variants: doc sach ky nang xa hoi. hieu va ((tham thuc) or (am thuc)) han danh viet cua tre*.