Maybe the trick is to leave some food (like diced and crushed fruit, unsalted peanuts in the shell, or mealworms) where they hang out when you see them? Them being out of your sight doesn’t necessarily mean you’re out of their sight. They could be watching nearby. If they’re in the area often, they’ll probably find it. Maybe if you put up some feeders that have crow-friendly foods closer to the house, they’ll warm up to it and you, You could also try leaving some food out for them a ways away and just hanging out for awhile reading or something, then gradually over time, leave the food closer.