Angularjs reload xml data after updating

See more:

PHP

AngularJs

Hi ,
I am using angularjs + php. In my function i use the code:
$scope.addComment = function()
{
var request = $http({
method: "post",
url: "xmlAction.php",
data: {
id:shopItemID,
functionname: 'addNewComment',
description: 'Description Comment',
name:'Alex'
},
headers: { 'Content-Type': 'application/x-www-form-urlencoded' }
});
loadComment();
};
function loadComment(){
services.getComments().then(function(data){
var source = x2js.xml_str2json(data.data);
var comments = ($filter('filter')(source.data.comment, {itemID: shopItemID }));

$scope.comments = comments;
});
};

After i call function addComment, it still loads xml data in cache. How can i clear xml data in cache and reload it again ?

Thanks.