Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
nam thuc » nam thuoc, am thuc, nam thu
cau treo » cau theo, cau tren, cau triet
tang ma » mang may, tang van
tang xa » trang xa, lang xa, tang ha
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
thuc ca » thuc cua, thuc can, thuc cao
dan vai » dan va, dan vat, den vai
dan tai » van tai, dan thi, han tai
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 ((tang xa) OR (tang ma)) hoi. hieu va nam thuc ca ((dan vai) or (dan tai)) cau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky ((tang xa) OR (tang ma)) hoi. hieu va nam thuc ca ((dan vai) OR (dan tai)) cau treo.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky ((tang xa) OR (tang ma)) hoi. hieu va nam thuc ca ((dan vai) or (dan tai)) cau treo".
• Adding a wildcard symbol may retrieve word variants: toc sach ky ((tang xa) OR (tang ma)) hoi. hieu va nam thuc ca ((dan vai) or (dan tai)) cau treo*.