Почему CURL возвращает только true?

$url = "https://www.jab.de/ru/ru/productsearch";
$cookie = "cookie.txt";

$ch = curl_init();

curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookie);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookie);

curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$response = curl_exec($ch);
if (curl_errno($ch)) die(curl_error($ch));

phpQuery::newDocument($response);
$token = pq("meta[name=_csrf]")->attr('content');

curl_setopt($ch, CURLOPT_POST, true);

$params = array(
    'facet' => '',
    'location' => "",
    'pageSize' => 30,

    'resultsNew' => 30,
    'resultsDisplayed' => 30,

    'searchTerm' => '',
    'sortCode' => "recommendation",
);
curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($params));

$headers = array (
    "Connection: keep-alive",
    "User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.19 (KHTML, like Gecko) Chrome/18.0.1025.162 Safari/535.19",
    "Accept: application/json, text/javascript, */*; q=0.01",
    "Accept-Encoding: gzip, deflate, br",
    "Accept-Language: ru-RU,ru;q=0.9,en;q=0.8,en-GB;q=0.7,en-AU;q=0.6,en-US;q=0.5",
    "Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3",
    "Content-Type: application/json; charset=UTF-8",
    "CSRFToken: $token",
    "X-Requested-With: XMLHttpRequest",
);
curl_setopt ( $ch, CURLOPT_HTTPHEADER, $headers );
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);

$html = curl_exec($ch);
var_dump($html);

if (curl_errno($ch)) print curl_error($ch);
curl_close($ch);