Scouring rewards

I'm really new to the game, this is like my second day playing, so sorry if this is an obvious question! I'm sending my Pokemon to scour in his preferred area, and each time he's bringing back nothing. The wiki shows that no Pokemon has more potential than another, and lists the rewards, but are the possible rewards just rng? Do I need to keep sending him out (given his energy allows it) and hope for the best? Thank you in advance whoever responds!

Yep! Just keep sending him out. To boost the chances of getting something better, buy the scour slots and scour boost which you can buy 2 of each

Thank you so much! Monferno and I have a big day of scouring ahead then. :P