Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thuc ban » thuoc ban, thuc dan, thu ban
cam thuc » am thuc, nam thuc, cam thu
nang xa » lang xa, nang ma, mang xa
doi cua » dai cua, hoi cua
vai cua » dai cua, hai cua, lai cua
hieu ve » hieu va, hieu van
so sac » so sach, so dac
sac ky » cac ky, sai ky
ve cam » ve cham, ve cac, va cam

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: so sac ky ((nang xa) OR (nang x)) hoi. hieu ve cam thuc ban thanh ((vai cua) OR (doi cua)) tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sac ky ((nang xa) OR (nang x)) hoi. hieu ve cam thuc ban thanh ((vai cua) or (doi cua)) tre~".
• Adding a wildcard symbol may retrieve word variants: so sac ky ((nang xa) OR (nang x)) hoi. hieu ve cam thuc ban thanh ((vai cua) or (doi cua)) tre*.