using (ISession session = NHibernateHelper.OpenSession())
            {
                using (ITransaction transaction = session.BeginTransaction())
                {
                    session.QueryOver<T>().Where() // all ok

                }
            }

productRepository.ExecuteQuery(over =>
            {
                IQueryOver<Product> inOtherContext = over;
                inOtherContext.Where // where method not exists
            });

IQueryOver<Product, Product>