Perhaps you should try some spelling variations:
thanh van » thanh san, thanh toan, thanh phan
dau tien » van tien
cam thuc » am thuc, nam thuc, cam thu
va thanh » gia thanh, ban thanh, va tinh
nang ma » tang ma, nang cao, mang may
hieu ve » hieu va, hieu van
thuc va » thuc vat, thuc dan, thuc day
sang ma » tang ma, sang tao, mang may
van dau » van dao, phan dau
san ky » sang ky, van ky, dan ky
ve cam » ve cham, ve cac, va cam
tu san » thu san, tu ban, tu can

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu san ky ((sang ma) or (nang ma)) hoi. hieu ve cam thuc va thanh van dau tien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu san ky ((sang ma) OR (nang ma)) hoi. hieu ve cam thuc va thanh van dau tien.
• Adding a wildcard symbol may retrieve word variants: tu san ky ((sang ma) or (nang ma)) hoi. hieu ve cam thuc va thanh van dau tien*.