Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
thuc dan » thuc hanh, hoc dan, thuc vat
sach ty » sach y, sach tu, sach thu
hanh di » hanh vi, hanh de, hang di
thuc va » thuc vat, thuc day
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
sang ma » tang ma, nang ma, sang tao
di cua » dai cua, doi cua, de 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: su sach ty ((sang ma) or (mang may)) hoi. hieu ve nam ((thuc va) or (thuc dan)) hanh di cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((sang ma) OR (mang may)) hoi. hieu ve nam ((thuc va) OR (thuc dan)) hanh di cua viet.
• Adding a wildcard symbol may retrieve word variants: su sach ty ((sang ma) or (mang may)) hoi. hieu ve nam ((thuc va) or (thuc dan)) hanh di cua viet*.