Filter problem

HTML

<div class="m-portlet m-portlet--mobile">
							<div class="m-portlet__head">
								<div class="m-portlet__head-caption">
									<div class="m-portlet__head-title">
										<h3 class="m-portlet__head-text">
											Static Datatable
										</h3>
									</div>
								</div>
							</div>
							<div class="m-portlet__body">
								<!--begin: Search Form -->
								<div class="m-form m-form--label-align-right m--margin-top-20 m--margin-bottom-30">
									<div class="row align-items-center">
										<div class="col-xl-8 order-2 order-xl-1">
											<div class="form-group m-form__group row align-items-center">
												<div class="col-md-4">
													<div class="m-form__group m-form__group--inline">
														<div class="m-form__label">
															<label>
																Paid:
															</label>
														</div>
														<div class="m-form__control">
															<select class="form-control m-bootstrap-select m-bootstrap-select--solid" id="m_form_status">
																<option></option>
																<option value="0">FALSE</option>
																<option value="1">TRUE</option>
															</select>
														</div>
													</div>
													<div class="d-md-none m--margin-bottom-10"></div>
												</div>
												<div class="col-md-4">
													<div class="m-form__group m-form__group--inline">
														<div class="m-form__label">
															<label class="m-label m-label--single">
																Category:
															</label>
														</div>
														<div class="m-form__control">
															<select class="form-control m-bootstrap-select m-bootstrap-select--solid" id="m_form_type">
																<option></option>
																<option value="1">1</option>
																<option value="2">2</option>
																<option value="3">3</option>
																<option value="4">4</option>
																<option...

JavaScript

var DatatableColumnRenderingDemo= {
    init:function() {
        var t;
        t=$(".m_datatable").mDatatable( {
            data: {
                type:"remote", source: {
                    read: {
                        url: "http://localhost/default/callback.php"
                    }
                }
                , pageSize:10, serverPaging:!0, serverFiltering:!0, serverSorting:!0
            }
            , layout: {
                theme: "default", class: "", scroll: !1, footer: !1
            }
            , sortable:!0, pagination:!0, search: {
                input: $("#generalSearch"), delay: 400
            }
            , rows: {
                callback:function(t, a, e) {}
            }
            , columns:[ {
                field:"id", title:"#", sortable:!1, width:40, textAlign:"center", selector: {
                    class: "m-checkbox--solid m-checkbox--brand"
                }
            }
            , {
               width:60, sortable:!1, field:"photo_path", title:"photo_path", template:function(t) {
                 output='<div class="m-card-user m-card-user--sm"><div class="m-card-user__pic"><img src="'+t.photo_path+'" class="m--img-rounded m--marginless" alt="photo"></div></div>';
                   return output
                }
            }
            , {
                field:"title", title:"title", width:90, template:function(t) {
                    return t.title
                }
            }
            , {
                field:"keyword", title:"keyword", width:120, template:function(t) {
                    return t.keyword
                }
            }
            , {
                field:"price", title:"price", width:120, template:function(t) {
                    return t.price
                }
            }
            , {
                field:"category", title:"category", width:120, template:function(t) {
                  var a= {
                      1: {
                          title: "1",...