Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nam thu, nha thuoc
toc sach » doc sach, thuoc sach, nuoc sach
thuoc va » thuc va, thuoc ma, thuong va
hoc sach » hoc sinh, hoc cac, hoc anh
cau treo » cau theo, cau tren, cau triet
hieu va » lieu va, hieu qua
nang xa » lang xa, nang ma, mang xa
dan vai » dan va, dan tai, dan vat
vai cau » va cau, van cau, vai cac
va nam » van nam, ha nam, va nay
va dan » ca dan, va dao, va dau

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) or (hoc sach)) y ((nang xa) OR (nang x)) hoi. hieu va nam thuoc va dan vai cau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sach)) y ((nang xa) OR (nang x)) hoi. hieu va nam thuoc va dan vai cau treo.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) or (hoc sach)) y ((nang xa) OR (nang x)) hoi. hieu va nam thuoc va dan vai cau treo".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (hoc sach)) y ((nang xa) OR (nang x)) hoi. hieu va nam thuoc va dan vai cau treo*.