In an older post I have found a nice option of how to force to use OR instead of AND in the Advanced Search when we have 2 operators for a field..
Acc. to Webmaster's suggestion I added the code below to Client Scripts -> Table Specific -> List page -> Startup script:
$(":radio[name^='v_'][value='OR']").prop('checked', true);
Selection to "OR" works but using this server event starting list page displays empty list with "No records found" message so in order to get records it is necessary to push "search" button. I wonder if there is a way to display list page records with preselected advanced search defined values not pushing Search button - as usual?