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If you were just trying to see what tier a Pokemon is, you can type /dt pokemon to pull it up. Example:
If you're looking for a specific Pokemon, then once again, I don't see why you'd be looking for PU Pokemon in an Ubers format, or specifically searching for PU Pokemon without first choosing the PU format.
If you search for a tier instead of a pokemon name you can select it (e.g. PU or PUBL) and only Pokémon from that tier display. Probably what you're after?
I use this sometimes for ubers-based formats like Godly Gift or Mix & Mega.