Global searc of all datatables

HTML

<link rel="stylesheet" href="http://datatables.net/release-datatables/media/css/demo_page.css">
<link rel="stylesheet" href="http://datatables.net/release-datatables/media/css/demo_table.css">
<script src="http://datatables.net/release-datatables/media/js/jquery.dataTables.js"></script>
		<div>
    
    <table id="example1" class="display" cellspacing="0" width="100%">
				<thead>
					<tr>
						<th>Name</th>
						<th>Position</th>
						<th>Office</th>
						<th>Age</th>
						<th>Salary</th>
					</tr>
				</thead>
				<tfoot>
					<tr>
						<th>Name</th>
						<th>Position</th>
						<th>Office</th>
						<th>Age</th>
						<th>Salary</th>
					</tr>
				</tfoot>
				<tbody>
					<tr>
						<td>Jena Gaines</td>
						<td>Office Manager</td>
						<td>London</td>
						<td>30</td>
						<td>$90,560</td>
					</tr>
					<tr>
						<td>Haley Kennedy</td>
						<td>Senior Marketing Designer</td>
						<td>London</td>
						<td>43</td>
						<td>$313,500</td>
					</tr>
					<tr>
						<td>Tatyana Fitzpatrick</td>
						<td>Regional Director</td>
						<td>London</td>
						<td>19</td>
						<td>$385,750</td>
					</tr>
					<tr>
						<td>Michael Silva</td>
						<td>Marketing Designer</td>
						<td>London</td>
						<td>66</td>
						<td>$198,500</td>
					</tr>
					<tr>
						<td>Bradley Greer</td>
						<td>Software Engineer</td>
						<td>London</td>
						<td>41</td>
						<td>$132,000</td>
					</tr>
					<tr>
						<td>Angelica Ramos</td>
						<td>Chief Executive Officer (CEO)</td>
						<td>London</td>
						<td>47</td>
						<td>$1,200,000</td>
					</tr>
					<tr>
						<td>Suki Burks</td>
						<td>Developer</td>
						<td>London</td>
						<td>53</td>
						<td>$114,500</td>
					</tr>
					<tr>
						<td>Prescott Bartlett</td>
						<td>Technical Author</td>
						<td>London</td>
						<td>27</td>
						<td>$145,000</td>
					</tr>
					<tr>
						<td>Timothy Mooney</td>
						<td>Office...

CSS

#div1 {
                background: #FFFDE0;
                width: 49%;
                height: 50%;
                float: left;
            }
            #div2 {
                background: #E2FFE0;
                width: 49%;
                height: 50%;
                float: left;
            }
            #div-mid-spacer {
                width: 2%;
                height: auto;
                float: left;
            }

JavaScript

$(document).ready(function() {
	var oTable1 = $('#example1').dataTable();
	
	var oTable2 = $('#example2').dataTable();
	
	var oTable3 = $('#example3').dataTable();
	
	var oTable4 = $('#example4').dataTable();
	$('table.display tfoot th').each(
                  				function() {
                  					var title = $(this).text();
                  					$(this)
                  							.html(
                  									'<input type="text" placeholder="Search '+title+'" />');
                  				});
	$("#example1 tfoot input").keyup( function () {
	/* Filter on the column (the index) of this element */
	oTable1.fnFilter( this.value, $("tfoot input").index(this) );
	} );

	$("#example2 tfoot input").keyup( function () {
	/* Filter on the column (the index) of this element */
	oTable2.fnFilter( this.value, $("tfoot input").index(this) );
	} );
	
	$("#example3 tfoot input").keyup( function () {
	/* Filter on the column (the index) of this element */
	oTable3.fnFilter( this.value, $("tfoot input").index(this) );
	} );
	
	$("#example4 tfoot input").keyup( function () {
	/* Filter on the column (the index) of this element */
	oTable4.fnFilter( this.value, $("tfoot input").index(this) );
	} );

} );