Get List Items using rest api

Hello,

<script type="text/javascript">
        var url = _spPageContextInfo.siteAbsoluteUrl;

        $(document).ready(function () {
            GetEvents();
        })

        function GetEvents() {
            var listname = $('#hdnlstThoughtOfTheDay').val();
            $.ajax({
                url: url + "/_api/web/lists/getbytitle('" + listname + "')/items?$expand=ContentType",
                type: "GET",
                headers: { "Accept": "application/json;odata=verbose" },
                success: function (data, textStatus, request) {
                    alert(data);
                    var dataResults = data.d.results;
                    alert(dataResults[0].Title);
                },
                error: function (msg) {
                    alert("error:" + JSON.stringify(msg));
                }
            });
        }
    </script>

I tried using above code but its not working.

Always getting data.d as 'undefined' as there is already items in list to show.