Probably not on purpose, but if they're small enough to fit in it's mouth it might just 'accidentally' suck one up as it goes past...
I would worry, unless the doras is very small and the cories full size, especially as cories have a spine, either on the gill cover or their pectoral fin (I can't remember which!) which they can lock erect, so they get stuck in other fish's throats
I shouldn't think he'd be able to eat them at an inch long. I would think about possibly splitting them up sometime in the future though; like I said, I'd worry.