$re = '/(?s)<P .*?#0007\'>\s*(.*?)\s*<\/SPAN.*?<\/P>/m';
$str = 'Some random stuff not part of the matched substring...<P class=MsoNormal
style="MARGIN-BOTTOM: 0pt; LINE-HEIGHT: normal; TEXT-AUTOSPACE: ; mso-pagination: none; mso-layout-grid-align: none"><B><SPAN
lang=de
style=\'FONT-SIZE: 33pt; FONT-FAMILY: "TimesNewRoman,Bold","serif"; mso-bidi-font-family: "TimesNewRoman,Bold"; mso-ansi-language: #0007\'>Teil
II<o:p></o:p></SPAN></B></P>and even more blub';
preg_match_all($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