Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nam thu, nha thuoc
doc sach » hoc sach, toc sach, nuoc sach
thuoc ma » hoc ma, duoc ma
cau treo » cau theo, cau tren, cau triet
dau tren » dau tien, dat tren, dau tieng
sach ty » sach y, sach tu, sach thu
ty lang » tay lang, ty xang, ty hang
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
dan vai » dan va, dan tai, dan vat
va nam » van nam, ha nam, va nay
ma dan » mat dan, mua dan, ca dan

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: doc sach ty lang xa hoi. hieu va nam thuoc ma dan vai ((cau treo) or (dau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach ty lang xa hoi. hieu va nam thuoc ma dan vai ((cau treo) OR (dau tren)).
• Adding a wildcard symbol may retrieve word variants: doc sach ty lang xa hoi. hieu va nam thuoc ma dan vai ((cau treo) or (dau tren))*.