Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
toc sach » hoc sach, doc sach, nuoc sach
nam thuc » nam thuoc, am thuc, nam thu
ty lang » tay lang, ty xang, ty hang
lang xa » lang ha, dang xay, lang van
qua nam » quan nam, cua nam, quang nam
thuc va » thuc vat, thuc dan, thuc day
danh di » danh du, xanh di, danh dien
hanh de » hanh ve, hanh kem
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: ((toc sach) OR (thuoc sach)) ty lang xa hoi. hieu qua nam thuc va ((danh di) or (hanh de)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (thuoc sach)) ty lang xa hoi. hieu qua nam thuc va ((danh di) OR (hanh de)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (thuoc sach)) ty lang xa hoi. hieu qua nam thuc va ((danh di) or (hanh de)) cua tre".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) OR (thuoc sach)) ty lang xa hoi. hieu qua nam thuc va ((danh di) or (hanh de)) cua tre*.