Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
cau treo » cau theo, cau triet, cau trieu
nay thuc » nam thuc, cay thuc, day thuc
cau tren » cu tren, dau tren, ca tren
tang ma » mang may, tang van
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
tang xa » trang xa, lang xa, tang ha
thuc va » thuc vat, thuc dan, thuc day
dan vat » dang vat, van vat, dan va
va dan » ca dan, va dao, va dau
va nay » va ngay, va cay

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 ky ((tang xa) or (tang ma)) hoi. hieu va nay thuc va dan vat ((cau treo) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ky ((tang xa) OR (tang ma)) hoi. hieu va nay thuc va dan vat ((cau treo) OR (cau tren)).
• Adding a wildcard symbol may retrieve word variants: thuoc sach ky ((tang xa) or (tang ma)) hoi. hieu va nay thuc va dan vat ((cau treo) or (cau tren))*.