How to do addAll from multiple sql result in hibernate?

How to do addAll from multiple sql result in hibernate?

I'm running sql seperately, because hibernate doesn't support "union". So
how to do addAll from those results.
public List<Product> findlist(String pid) {
List <Product> result1 ;
List <Product> result2;
Object[] obj = {pid};
result1.add(findAllByQuery(PRODUCT_DIVISION1,obj));
result1.add(findAllByQuery(PRODUCT_DIVISION2,obj));
return result1.addAll(result1);
}
PRODUCT_DIVISION1 = "query"; PRODUCT_DIVISION2 = "query";
Please advise.