Feed them their veggies at the same time every day, at the time you're wanting to see them. They'll eventually start waking up earlier for their dinner but it takes time for them to get used to it. You can also rustle the substrate a bit - I do this with mine if I want them to wake up. It's a nice slow way of getting them out of bed instead of stroking them or picking them up when they're asleep. It sounds like you haven't had them that long so they're probably still getting used to things. Robos aren't the most interactive hamsters and are usually more of a watching sort of hamster. They're the newest species to the pet industry so they aren't that accustomed to handling due to their strong wild instincts. Although that being said it is still possible to handle them and get them more tame and used to human contact
It takes a lot of time and patience but I'm sure you'll get there.