Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
cham thuc » nham thuc, pham thuc, tham thuc
thuc luat » thue luat, thuc luan, thuoc luan
luat canh » luat doanh, luat kinh, luc canh
hieu van » hieu va, thien van, lieu va
van cham » van chat, van tham, va cham
canh dai » can dai, canh dan, vanh dai
sach ty » sach y, sach tu, sach thu
hang xa » hoang xa, hang va, lang xa
hang ca » hang va, nang cao, hang tai
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: thuoc sach ty ((hang xa) or (hang ca)) hoi. hieu van cham thuc luat canh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ty ((hang xa) OR (hang ca)) hoi. hieu van cham thuc luat canh dai cua tre.
• Adding a wildcard symbol may retrieve word variants: thuoc sach ty ((hang xa) or (hang ca)) hoi. hieu van cham thuc luat canh dai cua tre*.