Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
thuc dan » thuc hanh, hoc dan, thuc vat
cau treo » cau theo, cau tren, cau triet
tay hoi » tay ho, tao hoi, tay thai
xay hoi » xa hoi, cay phoi, gay thoi
sach ty » sach y, sach tu, sach thu
thuc va » thuc vat, thuc day
ty dang » ty xang, ky dang, ty hang
dan va » doan va, dan ca, ban va
va cau » van cau, va cac, va dau
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 ty dang ((xay hoi) or (tay hoi)). lieu va nam ((thuc va) or (thuc dan)) dan va cau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty dang ((xay hoi) OR (tay hoi)). lieu va nam ((thuc va) OR (thuc dan)) dan va cau treo.
• Adding a wildcard symbol may retrieve word variants: toc sach ty dang ((xay hoi) or (tay hoi)). lieu va nam ((thuc va) or (thuc dan)) dan va cau treo*.