это ответ:
$url = 'https://example.url?';
// http_build_query builds the query from an array
$query_array = array (
'search' => $string,
'from' => $from,
'to' => $to,
'format' => 'json'
);
$query = http_build_query($query_array);
$result = file_get_contents($url . '&' . $query);