$re = '/(?:\([A-Z]+\))?FS[A-Z ]*-\d(?:[^\n,()-]*\w)?/m';
$str = 'Fakturasadas : (S)FSK-69/23/GFK/12hjkhjkddddd
(S)FSK-69/23/GFK/12S Z (S)FSK-69/23/GFK/ 1 2 .)
FS-1195,1196,1197,2072,2073/24/GF/02, (S)FS-1195/24/GF/02, (S)FS-1196/24/GF/02, (S)FS-1197/24/GF/02, (S)FS-2072/24/GF/02, (S)FS-2073/24/GF/02 (S)FSK-69/23/GF/12
(S)FS-1499/24/GF/01 (S)FS-1500/24/GF/01
I mean if invoice number : FS -444 4/23/F/11 - it also correct to: FS-4444/23/F/11, or FS-4444g/23g/F/1g1';
preg_match_all($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