$re = '/h1>(.+?)\s*\((\d*)\)<(?s).+?h2>(.+?)</';
$str = '
<h1>valami szöveg1 (0000)</h1>
<h2>valami szöveg2</h2>
';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php