Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
thuc day » thuc dan, thuc vat
vat cuu » vat cua
dan vat » dang vat, van vat, dan va
thuc va » thuc vat, thuc dan
cuu tre » cua tre, cau tren, cau treo
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
xay hoi » tay hoi, cay phoi, gay thoi
ky dang » ky nang, ky danh
va nam » van nam, ha nam, va nay

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 ky dang ((xay hoi) or (xa hoi)). hieu va nam ((thuc va) or (thuc day)) dan vat cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky dang ((xay hoi) OR (xa hoi)). hieu va nam ((thuc va) OR (thuc day)) dan vat cuu tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ky dang ((xay hoi) or (xa hoi)). hieu va nam ((thuc va) or (thuc day)) dan vat cuu tre*.