Try this out to search for a time interval based on the actual_time.
| eval _time=actual_time
| search earliest=<epoch_time> latest=<epoch_time>
If the actual-time is not in epoch, you must convert it before the search command:
| eval _time=strftime(actual_time, "%Y-%m-%d %H:%M:%S")
If this was helpful, some karma would be appreciated.