function createCORSRequest(method, url) {
  var xhr = new XMLHttpRequest();
  if ("withCredentials" in xhr) {
    // XHR for Chrome/Firefox/Opera/Safari.
    xhr.open(method, url, true);
  } else if (typeof XDomainRequest != "undefined") {
    // XDomainRequest for IE.
    xhr = new XDomainRequest();
    xhr.open(method, url);
  } else {
    // CORS not supported.
    xhr = null;
  }
  return xhr;
}

 var produkty = ["006184"]
    $.each (produkty, function (k,v){

        var nr_sklepow = ["710"]
            $.each (nr_sklepow, function (n,w) {

                // Make the actual CORS request.
                function makeCorsRequest() {
                  // This is a sample server that supports CORS.
                  var url = 'https://www.jula.pl/catalog/narzedzia-i-maszyny/elektronarzedzia-i-maszyny/wkretarki/wkretarki-akumulatorowe/zestaw-narzedzi-one-006184/GetWareHouseStock/';

                    var vars = {
                    data.append('storecode', w);
                    data.append('productCode', v);
                }
                data.append(vars)

                  var xhr = createCORSRequest('POST', url);
                  if (!xhr) {
                    alert('CORS not supported');
                    return;
                 }

                  // Response handlers.
                  xhr.onload = function() {
                    var text = xhr.responseText;
                    /*var json = JSON.parse(text);
                    console.log(json)*/
                  };

                  xhr.onerror = function() {
                    console.log('Woops, there was an error making the request.');
                  };

                  xhr.send(data);
                }

                makeCorsRequest()
        })
    })