Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
nam thuc » nam thuoc, am thuc, nam thu
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
hieu he » hieu ve, hiem he, hieu le
su sach » so sach, vu sach
tang ma » tang van
he nam » ha nam, nghe nam
vi cua » vai cua, di 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) or (vu bach)) ty ((tang ma) or (mang may)) hoi. hieu he nam thuc va hanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu bach)) ty ((tang ma) OR (mang may)) hoi. hieu he nam thuc va hanh vi cua viet.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (vu bach)) ty ((tang ma) or (mang may)) hoi. hieu he nam thuc va hanh vi cua viet*.