Use html2pdf for multilingual.
I tried with this and it worked for me.I developed site for (English/Japanese)
Used font arialunicid0 for multilingual.
require_once('Classes/library/html2pdf.class.php');
//$html2pdf = new HTML2PDF('P', 'A4', 'en');
$html2pdf = new HTML2PDF('P', 'A4', 'en', true, 'UTF-8');
$html2pdf->setDefaultFont('arialunicid0');
$html2pdf->pdf->SetDisplayMode('fullpage');
$html2pdf->writeHTML($content, isset($_GET['vuehtml']));
$filename = $filename .'_'.date('Ymd');
$html2pdf->Output($filename.'.pdf','D');
It download file with Japanese text.
Only problem I facing here with file name.
IF I pass Japanese character for file name it downloads file with blank name.