Perhaps you should try some spelling variations:
thuc dayt » thuc vat, thuc dan, thuc xay
cua viet » ca viet, hoa viet, cua vat
thuc day » thuc dan, thuc vat
so sach » so sanh, bo sach, co sach
dai hoi » dai hoc, dai hai, dai moi
da nang » cam nang, kha nang, cao nang
va nang » van nang, cam nang, kha nang
hieu ve » hieu va, hieu van
ve cam » ve cham, ve cac, va cam
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: so sach ((va nang) or (da nang)) dai hoi. hieu ve cam ((thuc day) or (thuc dayt)) hanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((va nang) OR (da nang)) dai hoi. hieu ve cam ((thuc day) OR (thuc dayt)) hanh vi cua viet.
• Adding a wildcard symbol may retrieve word variants: so sach ((va nang) or (da nang)) dai hoi. hieu ve cam ((thuc day) or (thuc dayt)) hanh vi cua viet*.