Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
sach kem » hanh kem
danh dai » danh dau, danh di, danh sai
sach ky » sac ky, sach ty, sach hay
xay hoi » xa hoi, tay hoi, cay phoi
hieu va » lieu va, hieu qua
va tham » van tham, va cham, va thanh
thuc va » thuc vat, thuc dan, thuc day
va danh » va dinh, va dan, va hanh
cua tre » cua te, cuu tre, cua triet

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 ky) OR (sach kem))) or (sach y)) van xay hoi. hieu va tham thuc va danh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((((sach ky) OR (sach kem))) OR (sach y)) van xay hoi. hieu va tham thuc va danh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((((sach ky) OR (sach kem))) or (sach y)) van xay hoi. hieu va tham thuc va danh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((((sach ky) OR (sach kem))) or (sach y)) van xay hoi. hieu va tham thuc va danh dai cua tre*.