Perhaps you should try some spelling variations:
sach van » sach han, sach va, cach van
bach van » bach dan, cach van, bach dang
cam thuc » am thuc, nam thuc, cam thu
thuc van » thuc vat, thuc dan, thuc va
van hanh » van thanh, ban hanh, van anh
hieu ve » hieu va, hieu van
hanh de » hanh ve, hanh kem
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam
de cua » le cua, te cua, dieu cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach van) or (bach van)) nang x ho. hieu ve cam thuc van hanh de cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach van) OR (bach van)) nang x ho. hieu ve cam thuc van hanh de cua tre.
• Adding a wildcard symbol may retrieve word variants: su ((sach van) or (bach van)) nang x ho. hieu ve cam thuc van hanh de cua tre*.