Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
sach ky » sac ky, sach ty, sach kem
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
danh di » danh du, xanh di, danh dien
cua tre » cua te, cuu tre, cua triet
di cua » dai cua, doi cua, de 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 ky) or (sach y)) van xay hoi. hieu va tham thuc va danh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sach y)) van xay hoi. hieu va tham thuc va danh di cua tre.
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) or (sach y)) van xay hoi. hieu va tham thuc va danh di cua tre*.