To find a specific enemy on the Veldt, follow these steps:
For example, I'm trying to find HellRidr, which I can see from using "CTRL-F/Find" that it's only in formation #10. I go onto the Veldt and encounter a solo SoulEatr, so I know that I'm in formation #61. I fight 12 more battles after that, so my last battle was an encounter in formation #9 (62, 63, 0-9). I perform a save state, then fight a battle on the Veldt, but run into 3x LivingDe. That's not what I want, so I reload the save state, then go fight a battle off of the Veldt. I come back and, luckily, encounter HellRidr on my first battle afterwards. I can now cross HellRidr off of my Rages list.