You can use the Web Services in SharePoint 2013 Workflows in SharePoint Designer 2013 to query the lists api or to query the search api (or any of the sharepoint REST API) . Follow this: https://msdn.microsoft.com/en-us/library/office/dn567558.aspx

[![enter image description here][1]][1]

You need to query several lists, so I recommend using to search api to query by the event content type as described here: 

http://sharepoint.stackexchange.com/questions/115941/how-to-get-all-items-with-a-specific-content-type-using-rest-api

Query including your 3,4 keywords.

You also need to run workflow continuosly, daily basis. You can achieve this by seeting up a event timer job if you have access/permissions to do this on server side, and if you don't, you create your workflow with a 24h pause stage. http://sharepoint.stackexchange.com/questions/138098/schedule-a-workflow-to-run-everyday/138104 

Hope this helps.

  [1]: https://i.sstatic.net/Rq0Jj.png