Perhaps you should try some spelling variations:
bai phoi » bai choi, bai hoc, dai hoi
thuc dan » thuc hanh, hoc dan, thuc vat
hanh vai » hanh vi, hanh va, hanh tai
cua viet » ca viet, hoa viet, cua vat
thuc va » thuc vat, thuc day
vai cua » dai cua, hai cua, lai cua
ky va » ly va, ke va, my va
hien » bien, tien, dien

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu cac ky va bai phoi. hieu ((vien dai) or (hien dai)) ((thuc va) OR (thuc dan)) hanh vai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cac ky va bai phoi. hieu ((vien dai) OR (hien dai)) ((thuc va) OR (thuc dan)) hanh vai cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac ky va bai phoi. hieu ((vien dai) or (hien dai)) ((thuc va) OR (thuc dan)) hanh vai cua viet".
• Adding a wildcard symbol may retrieve word variants: tu cac ky va bai phoi. hieu ((vien dai) or (hien dai)) ((thuc va) OR (thuc dan)) hanh vai cua viet*.