Reterieving data from firebasedatabase

Question

Hey I have a problem when retrieving data from firebasedatabase using arabic values at orderbychild or value or equal to methods it return null.I have searched deep but didn't succeed.So I hope some of you may have solved such a problem. the code I am using

 ValueEventListener valueEventListener=new ValueEventListener() {
    @Override
    public void onDataChange(@NonNull DataSnapshot dataSnapshot) {

        for (DataSnapshot postSnapshot: dataSnapshot.getChildren()) {
            Package nm=postSnapshot.getValue(Package.class);
            mpostSnapshot.add(nm);
        }
    }

    @Override
    public void onCancelled(@NonNull DatabaseError databaseError) {

    }
};

Query MQ=FirebaseDatabase.getInstance().getReference("donors").orderByChild("gov")
        .equalTo("بني سويف");

MQ.addListenerForSingleValueEvent(valueEventListener);