When you open LCS Environment monitoring, navigate to tab page Activity, select Query name "All logs", you have option Show query options. This allows you to add search criteria for specific telemetry fields. This does not work however.

For example adding row for field formName, Operator Equals, Value SalesTable does not return any rows, even though there are many events in the logs for form name SalesTable. Other fields also do not work. It seems the Query is ignored and system only uses what's in the Start and End date fields and the Search terms box.

It would really help customers and partners troubleshooting issues in their production environments if you would allow them to apply filters to reduce the number of log events, and prevent unnecessary requests to Microsoft support.