Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
cua thuoc » nha thuoc, cay thuoc, cua nuoc
dang xay » dang van, van xay
vat hanh » vat thanh, van hanh, va hanh
te sach » toc sach
lang xa » lang ha, lang van
hieu ve » hieu va, hieu van
ve cham » va cham, ve chat, vu cham
cua tuc » cua duc, cua tu, luat tuc

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

• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y ((lang xa) OR (dang xay)) hoi. hieu ve cham thuc vat hanh vi ((cua tuc) OR (cua thuoc))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y ((lang xa) or (dang xay)) hoi. hieu ve cham thuc vat hanh vi ((cua tuc) OR (cua thuoc))~".
• Adding a wildcard symbol may retrieve word variants: te sach y ((lang xa) or (dang xay)) hoi. hieu ve cham thuc vat hanh vi ((cua tuc) OR (cua thuoc))*.