I am quite new to SharePoint 2013 and I have been working lately with the Content Search Web Part. However I haven't been able to make possible a filtering through a custom column that I have on a specified document library. Can someone guide me to settle up the CSWP so that the custom column can appear on the Query Filter in Advanced Options?
To be in context: I have a Document Library called 'Files'. That document library has the predefined columns (Title, Description, dateCreated), and I have added a new column named 'Topic' which is of type 'Choice' (menu to choose from). I want my search filter to throw back the files that contain one of the options of this column. I'll appreciate a lot any help. Thanks!