Perhaps you should try some spelling variations:
thuc day » thuc dan
cua viet » ca viet, hoa viet, cua vat
te sach » toc sach
sach ty » sach y, sach tu, sach thu
ty dang » ty xang, ky dang, ty hang
dang xa » dang xay, lang xa, dang ha
hieu vu » hieu va, hieu ve, hieu su
vu pham » su pham, vi pham, vu kham
hanh va » hang va, hanh vi
va cua » va chua, via cua, ca cua

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 ty dang xa hoi. hieu vu pham ((thuc day) OR (thuc vat)) hanh va cua viet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty dang xa hoi. hieu vu pham ((thuc day) OR (thuc vat)) hanh va cua viet".
• Adding a wildcard symbol may retrieve word variants: te sach ty dang xa hoi. hieu vu pham ((thuc day) OR (thuc vat)) hanh va cua viet*.