function searchFiles($dir, $startDate, $endDate, $searchTerm) {
  $files = glob($dir . '/*');
  $result = array();

  foreach($files as $file) {
    if(is_dir($file)) {
      $result = array_merge($result, searchFiles($file, $startDate, $endDate, $searchTerm));
    } else {
      if(preg_match("/$searchTerm/", basename($file))) {
        $fileTime = filemtime($file);
        if($fileTime >= $startDate && $fileTime <= $endDate) {
          $result[] = $file;
        }
      }
    }
  }

  return $result;
}


$dir = '/path/to/directory';
$startDate = strtotime('2022-01-01');
$endDate = strtotime('2022-12-31');
$searchTerm = 'myfilename';

$result = searchFiles($dir, $startDate, $endDate, $searchTerm);

foreach($result as $file) {
  echo $file . "\n";
}