Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
hai cua » thai cua, dai cua, hoi cua
va danh » va dinh, va dan, dia danh
va hanh » van hanh, va thanh, ban hanh
te sach » toc sach
hieu he » hieu ve, hiem he, hieu le
hoa hoi » khoa hoi, hoa hoc, hoa doi
ky lang » ky dang, ky tang, tay lang
he am » he nam, ve am

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ((ky lang) or (ky nang)) hoa hoi. hieu he am thuc ((va hanh) OR (va danh)) hai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((ky lang) OR (ky nang)) hoa hoi. hieu he am thuc ((va hanh) OR (va danh)) hai cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((ky lang) or (ky nang)) hoa hoi. hieu he am thuc ((va hanh) OR (va danh)) hai cua viet".
• Adding a wildcard symbol may retrieve word variants: te sach ((ky lang) or (ky nang)) hoa hoi. hieu he am thuc ((va hanh) OR (va danh)) hai cua viet*.