After Robbie adds the Shrine Sensor to your Purah Pad, you can gather data so Robbie can unlock the Sensor + feature.

Quest Location

This quest is available from Robbie after you complete the quest Hateno Village Research Lab.

Take Pictures of Five Different Monsters

If you haven't already done so, you can go around Hyrule and take pictures of five different types of monsters. After that, you can come back and talk to Robbie. He will add the Sensor + feature, which allows you to select anything from the Hyrule Compendium for Sensor + to search for. Robbie will put up a poster with instructions on how to use the Sensor + feature.

You can check on the compendium database machine on the table to start the side adventure Filling Out the Compendium. You can check on the database machine any time, and Robbie will list the categories of pictures that you can purchase.