In order to discover something with a wildcard, you will need to program the known talkgroups ahead of time and store them in a disabled scan list, or skip/lockout, so that the scanner will know that they have already been identified and will ignore them. It only works if you are scanning. It does not work if you are just paused/holding on the wildcard itself.
If you want to skip/lockout a talkgroup, you will need to add it to the scanner's memory while it is active by going into the Menu and selecting "Store Wildcard". This adds the talkgroup to the same scan list that the wildcard is in. You will then be able to skip/lockout that talkgroup, or move it to the disabled scan list, so that the wildcard will ignore it in the future.