Perhaps you should try some spelling variations:
thien van » thi van
toc sach » hoc sach, doc sach, thuoc sach
thuc dan » thuc hanh, thuc vat
sach ky » sac ky, sach y, sach ty
cuu tre » cua tre, cau tren, cau treo
thuc va » thuc vat, thuc day
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
van am » van nam, van lam, van dam
dan va » doan va, dan ca, ban va
va cuu » va cau, va chu, va huu

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 lang xa hoi. thien van am ((thuc va) or (((thuc dan) OR (hoc dan)))) dan va cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky lang xa hoi. thien van am ((thuc va) OR (((thuc dan) OR (hoc dan)))) dan va cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky lang xa hoi. thien van am ((thuc va) or (((thuc dan) OR (hoc dan)))) dan va cuu tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ky lang xa hoi. thien van am ((thuc va) or (((thuc dan) OR (hoc dan)))) dan va cuu tre*.