Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
hieu van » thien van, lieu va
vat danh » va danh, van danh, luat danh
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
ky tang » ky nang, ky dang, kho tang
tang xa » trang xa, tang ma, lang xa
hieu va » lieu va, hieu qua
danh vi » hanh vi, dinh vi, danh di
vi hoa » voi hoa, vi hoc, va hoa

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky tang xa hoi. ((((hieu ve) OR (hieu va))) OR (hieu van)) cham thuc vat danh vi hoa viet~.
• Adding a wildcard symbol may retrieve word variants: su sach ky tang xa hoi. ((((hieu ve) or (hieu va))) or (hieu van)) cham thuc vat danh vi hoa viet*.