DomPDF help!!

[eluser]andregufc[/eluser]
I'm from Portugal, and i can't speack english, my english is not good, but please help me.

I have a form with results of a search, and have one checkbox for each result.

If I select more of 5 results, the pdf not display.

My code:

*************************************************
$this->load->plugin('to_pdf');
$sql='WHERE';
foreach($_POST['opcoes'] as $selecionados){
$sql .= ' Imo_Codigo=\''.$selecionados.'\' OR ';
}
$dados['results'] = $this->db->query('SELECT * FROM Imovel '.$sql.'Imo_Codigo = \'FINALIZA_OR\'');
$html = $this->load->view('cadimobiliario_modoficha', $dados, true);
pdf_create($html, 'Pesquisa Imovel', 'landscape');

*************************************************

if i select 1,2,3,4 or 5 results, the pdf is displayed ok.

Whats the problem? Performance? DomPDF? My Code?

Thx very much!