When you use a search expression in Search or Top N to discover entries, you may unexpectedly find that no results are returned.
Search and Top N search expressions only work with indexed attributes
Release : 1.4.1
You must use indexed attributes for Search or Top N search expressions. The list of searchable event attributes can be found in the following article:
Once there are search results, another filter field will be available and you can further filter using the Filter expression. The Filter expression uses all fields for greater filtering flexibility. More information on Filters can be found in this article: