Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
hanh dai » hanh tai, hanh dao, vanh dai
thuc dan » thuc hanh, hoc dan, thuc vat
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
co viet » so viet, o viet, hoc viet
thuc va » thuc vat, thuc day
hieu ve » hieu va, hieu van
ty nang » ky nang, ty xang, ty hang
nang o » nang co, nang ho, nang ro
ve am » va am
o hoc » co hoc, mo hoc, so hoc

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang o hoc. hieu ve am ((thuc va) OR (thuc dan)) hanh dai ((va triet) OR (co viet))~.
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang o hoc. hieu ve am ((thuc va) or (thuc dan)) hanh dai ((va triet) or (co viet))*.