Why does my search does not work ?

hcha

Hi,
My datatable is filled by a JSon source returned by an Ajax request (server side processing).
I add a input type text to search among values of a column but it does not work...
Here is how my datatable is initialised in my .jsp page

        $('#table_events').DataTable({
                serverSide: true,
                processing: true,
                ordering: false,
                paging: true,
                scrollY: '75vh', // vh unit is a percentage of the browser window height
                deferRender: true,
                scrollCollapse: true,
                searching: true,
                //stateSave: true,   // Keeps scroller position in case of page reloading
                ajax: {
                    url: "/elogs/proposalEvents/reloadData",
                    type: "GET"
                },
                scroller: {
                    loadingIndicator: true,
                    serverWait: 250,
                    displayBuffer: 25,  
                    boundaryScale: 0.75
                },
                language: {
                    loadingRecords: "Please wait : loading data...",
                    processing: "Please wait : loading data..."
                },
                "aoColumns": [{"sType":"string"}],                  
                "aoColumnDefs": [
                                       {"bVisible": false, "aTargets": [3], "searchable": true},    
                                       {"bVisible": false, "aTargets": [4], "searchable": false}    
                                    ]                   
        });

My input type text is :

<input type="text" id="search-input-text">

And the code to trigger the search is :

    var table = $('#table_events').DataTable();

$('#search-input-text').on('keyup', function () {
             var family =$(this).val();  // getting search input value
             table.columns(3).search(this.value).draw();
});

Thanks in advance for your help !