$re = '/a[\s]+href="[^mailto][\S]+polskieszlaki\.pl(.*)(\?)(.*)\"/iU';
$str = '<a href="http://www.polskieszlaki.pl" style="color: #09173b; text-decoration: none;"></a>
<a href="http://www.polskieszlaki.local/wawel-w-krakowie.htm?utm_source=2017-06-13&utm_medium=email" >
<a href="http://www.polskieszlaki.pl/zamek-w-pszczynie.htm?utm_source=2017-06-13&utm_medium=email&utm_campaign=newslettery&utm_content=atrakcje-zamek-w-pszczynie">
<a href="http://www.polskieszlaki.pl/?asas">asaaS</a>
<a href="http://www.polskieszlaki.pl/wawel.htm">asaaS</a>
<a href="mailto:biuro@polskieszlaki.pl">
';
preg_match_all($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