select u from Representante u 
  where exists (select pj from PessoaJuridica pj where pj=u.pessoa and upper(pj.agrupamentoPJ.razaoSocial) like :descricao) 
  or exists (select pf from PessoaFisica pf where pf=u.pessoa and upper(pf.nome) like :descricao)

SELECT t0.ID, t0.DTYPE, t0.ATIVO, t0.OPTIMISTICLOCK, t1.ID, t1.PESSOA_ID, t2.ID, t2.ALCANCE, t2.CALCULOCOMISSAO, t2.COMISSAO, t2.DESCRICAO, t2.GERARCARGA, t2.LANC, t2.LIMITEDESCONTO, t2.LOTEPEDIDOS, t2.NOME, t2.NRPEDFINAL, t2.NRPEDINICIAL, t2.RECEBECOMISSAO, t2.SENHALIBERACAO, t2.STATUS, t2.TABELAPRECO_ID, t3.ID, t3.ALTERARPV, t3.SUPERVISOR, t3.ID_SUP 
FROM ESTGREPRESENTANTE t3, ESTGDISTRREPRES t2, ESTGENTIDADEINTEGRADAPESSOA t1, ESTGENTIDADEINTEGRADA t0 
WHERE ((EXISTS (SELECT ? 
                FROM GERPESSOAJURIDICA t5, GERPESSOA t4, GERAGRUPAMENTOPJ t6 
                WHERE ((((t4.ID = t1.PESSOA_ID) 
                   AND UPPER(t6.RAZAOSOCIAL) LIKE ?) 
                   AND ((t5.ID = t4.ID) 
                   AND (t4.DTYPE = ?))) 
                   AND (t6.NUMEROCNPJ = t5.NUMEROCNPJ))
               ) 
       OR EXISTS (SELECT ? 
                  FROM GERPESSOAFISICA t8, GERPESSOA t7 
  ======>>>>        WHERE (((t4.ID = t1.PESSOA_ID)   
                    AND UPPER(t8.NOME) LIKE ?) 
                    AND ((t8.ID = t7.ID) 
                    AND (t7.DTYPE = ?))))
        ) 
        AND (((t3.ID = t0.ID) 
        AND ((t2.ID = t0.ID) 
        AND (t1.ID = t0.ID))) 
        AND (t0.DTYPE = ?)))


ERROR:  missing FROM-clause entry for table "t4"
LINHA 13:                   WHERE (((t4.ID = t1.PESSOA_ID)