Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
thuc day » thuc dan, thuc vat
thuc va » thuc vat, thuc dan
hieu ve » hieu va, hieu van
so sanh » do sanh
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
sanh y » sinh y, anh y, hanh y
vi cua » vai cua, di cua
ve nam » he nam, va nam, le nam

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sanh y ((nang xa) or (lang xa)) hoi. hieu ve nam ((thuc va) OR (thuc day)) hanh vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sanh y ((nang xa) OR (lang xa)) hoi. hieu ve nam ((thuc va) OR (thuc day)) hanh vi cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sanh y ((nang xa) or (lang xa)) hoi. hieu ve nam ((thuc va) OR (thuc day)) hanh vi cua viet".
• Adding a wildcard symbol may retrieve word variants: so sanh y ((nang xa) or (lang xa)) hoi. hieu ve nam ((thuc va) OR (thuc day)) hanh vi cua viet*.