JSON API - IONIC (AngularJS)

Question

I'm extracting a JSON API URL in the framework ionic with AngularJs like the code below:

.factory('BuyApi', function($http) {
  var obj = {};

  obj.buy = function() {
    var api = "https://maiscarrinho.com/api/search?q=gato&pageNumber=0&pageSize=10";
    return $http.get(api);
  };
  return obj
})

.controller('MainControl', function($scope, BuyApi){

  $scope.produtos;

  BuyApi.buy().success(function(data) {
      $scope.data = data;
      $scope.produtos = data.results;
  })
});

For the JSON file I use this URL: https://maiscarrinho.com/api/search?q=gato&pageNumber=0&pageSize=10, but every time you do an refresh on the page data changes (more exactly the prices) and it does not happen in the actual site : https://maiscarrinho.com/search?q=gato.

So I did an investigation might it be because the request and response header? Do I need to pass parameter? or something?