Column specific search (Search API)

This doesn’t work out-of-the box with datatables plugin configuration. You have to create additional filter field or modify existing search field, that all has to be done with javascript as shown in your example (or another one: https://datatables.net/examples/api/multi_filter.html).

You can add javascript to your page via direct text editing (not HTML), or use external file and include it via theme in header/footer.

I managed it with this code:

var table = $('#table_example').DataTable();
table.columns( [6] ).search( searchterm ).draw();

– replace #table example with the table ID.
– 6 is the column number. counting starts with 0.