Add multiple DNS domains on the destination hosts field box to block websites through firewall policy

I an using SEP 12.1.6 (12.1 RU6 MP3). I am blocking several websites with the use of a firewall policy. I followed the instructions on this post: https://www.symantec.com/connect/forums/block-particular-website . I was wondering if there was a way to add several websites under one field box under the Host List? For example, DNS domain: *.facebook.com; *.yahoo.com; *.aol.com; and so on. I curently have a field box for each website.