Perhaps you should try some spelling variations:
chua thiet » chuan thiet, cua thiet, thua thiet
hieu van » thien van, lieu va, hieu ve
cham duc » pham duc, cham soc, pham duy
te sach » toc sach
ky sang » ky dang, ky tang, duy sang
hieu va » lieu va, hieu qua
va danh » va dinh, va dan, va hanh
danh vi » hanh vi, dinh vi, danh di
vi chua » va chua, vi khuan, chi chua
ma hoi » mai hoi, xa hoi, ma 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: te sach ((ky sang) OR (ky nang)) ma hoi. ((hieu van) OR (hieu va)) cham duc va danh vi chua thiet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((ky sang) OR (ky nang)) ma hoi. ((hieu van) or (hieu va)) cham duc va danh vi chua thiet~".
• Adding a wildcard symbol may retrieve word variants: te sach ((ky sang) OR (ky nang)) ma hoi. ((hieu van) or (hieu va)) cham duc va danh vi chua thiet*.