function get_multiple_keys($arr, $keys = []){
  if(!$keys) return [];
  $result = [];
  array_walk($keys, function($key, &$val = null) use ($arr, &$result){
      if(isset($arr[$key])){
          $result[$key] = $arr[$key];
      } 
  });
  return $result;
}

// Test
$res = get_multiple_keys(['name' => 'Victor', 'age' => 24, 3 => 'Hello world!'], ['name', 'age', 3, 10, 'aaaa']);
var_dump($res);

// Result
// -> array(3) { ["name"]=> string(5) "Victor" ["age"]=> int(24) [3]=> string(8) "Hello world" }