DataTables Filter Dropdown - Parse list, contains not exact - datatables

Question

So my javascript is bad, but I have a datatables need that I cannot figure out. Relevant code here:
$('#lesson-table').DataTable( {
'data': cleanData,
'paging': false,
'order': [[ 8, 'asc' ], [ 3, 'desc' ], [ 1, 'desc' ]],
initComplete: function () {
// this is where we populate the filter dropdowns
this.api().columns([0,1,2,6,7]).every( function () {
var column = this;
var select = $('<select><option value=""></option></select>')
.appendTo( $(column.header()) )
.on( 'change', function () {
var val = $.fn.dataTable.util.escapeRegex(
$(this).val()
);
column
.search( val ? '^'+val+'$' : '', true, false )
.draw();
} );
column.data().unique().sort().each( function ( d, j ) {
var val = $('<div/>').html(d).text();
select.append( '<option value="' + val + '">' + val + '</option>' );
} );
} );
}
} );
// this removes duplicate dropdown values
var usedNames = {};
$("#lesson-table select > option").each(function () {
if (usedNames[this.value]) {
$(this).remove();
} else {
usedNames[this.value] = this.text;
}
});
So the change that was made in my datasource is that columns 1, the second column in the set, is now a comma separated list of items. Most of the time it is one item say: "Entertainment", but sometimes it can be "Entertainment, Sports, Healthcare" At the moment, it will show that list as an option in my dropdown, but what I need it to do is split them up and then filter by contains...not by exact.
Hope that makes sense. Can explain more if needed.