Filter when users selects empty and some value

Harsh Damania

I am using Jquery Datatable in my application , where i am using column filters.
I have created my own custom multicheckbox column filters for each column , now in the filters for eg there is data like USA,INDIA,CHINA,Empty for country column.
When user selects Empty it should search for places where string is empty or null or no value in td.
I guess this works by using column.search('').draw();
but now my requirement is when user selects USA,INDIA and Empty it doesnt work

Here is the regex i am using ,
regex = ("\b" + selected.join('\b|\b') + '\b');
self.searchResult = regex;
column.search(regex, true).draw();

Thanks:-)