Perhaps you should try some spelling variations:
sach nuoc » sach duoc, cac nuoc, bach tuoc
cham thuc » nham thuc, pham thuc, tham thuc
vat hanh » vat thanh, van hanh, va hanh
sach dao » lanh dao
sach vuc » sach duoc, sach truc, sach bac
ve cham » va cham, ve chat, vu cham
hanh di » hanh vi, hanh de, hang di
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
di cua » dai cua, doi cua, de cua
x hoi » xa hoi, o hoi, x ho

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 vuc) OR (sach nuoc))) or (sach dao)) nang x hoi. hieu ve cham thuc vat hanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((((sach vuc) OR (sach nuoc))) OR (sach dao)) nang x hoi. hieu ve cham thuc vat hanh di cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((((sach vuc) OR (sach nuoc))) or (sach dao)) nang x hoi. hieu ve cham thuc vat hanh di cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((((sach vuc) OR (sach nuoc))) or (sach dao)) nang x hoi. hieu ve cham thuc vat hanh di cua tre*.