Hi guys! I got my boys a couple of months ago. It's my first time owning rats and I don't think I'm doing it right. I got them from a breeder, not a pet shop chain, and they were 3 months old when I got them. I've tried giving them space, slowly going up to them, introducing my hand slowly,  leaving used items of clothing so they'd get used to my smell, bathtub bonding etc. I don't think any of this is actually working. They don't really free roam either, whenever I put them outside of their cage they literally stay in the same spot for hours until its time to go back. One of them Is more curious, and will explore for a bit before choosing his designated corner. I love animals, so naturally this comes off as "scared" behavior, but I genuinely don't know why. I move slowly, never sudden movements, speak in a low volume, never loud noises in the room, and they don't seem to mind when I pick them up. They don't play with their toys either. Yesterday, i woke up to them making noises and I caught them play fighting, which made me happy because at least they were doing something? I don't know, they seem to be "homebodies" just lazy, not playing, not interested in interaction or pets or even treats. One of them won't eat from my hand, the other will take the food and hide, so giving them treats doesn't work either. I don't know what they like, its so ambiguous, one day they can eat it and the next be uninterested. I haven't found a treat they love enough for me to use to bond with them. I love my boys so much but I want them to love me back aswell. Is this normal? 

Pic added for the Rat tax, The one with the black suit is Quesito and the one with the Tan suit is Pudín 

My rats dont seem to be bonding with me