You can use Select by Filter to limit the scope to specific controllers or ranges of controllers, or use the exc[lude] check box which works like a logical "Not".
For reference, here's a screenshot showing two controller lanes for each of three horn tracks with channelized events plus a Sustain Pedal lane for the Piano track. You can see that Track 5 has focus, so its controllers are shown, while other lanes are grayed out, and the sustain pedal lane is empty because the Piano track is hidden.