Perhaps you should try some spelling variations:
nuoc sach » nguoi sach, hoc sach, cuoc cach
doc sach » hoc sach, toc sach, dac sac
cao thuc » cao thuoc, bao thuc, can thuc
hanh de » hanh ve, hanh kem
danh di » danh du, xanh di, danh dien
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
va cao » va cac, va co, va dao

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) OR (nuoc sach)) ky nang xa hoi. hieu va cao thuc vat ((danh di) or (hanh de)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doc sach) OR (nuoc sach)) ky nang xa hoi. hieu va cao thuc vat ((danh di) OR (hanh de)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doc sach) OR (nuoc sach)) ky nang xa hoi. hieu va cao thuc vat ((danh di) or (hanh de)) cua tre".
• Adding a wildcard symbol may retrieve word variants: ((doc sach) OR (nuoc sach)) ky nang xa hoi. hieu va cao thuc vat ((danh di) or (hanh de)) cua tre*.