I didn't watch the videos so I don't know if this is mentioned or not, but a great way to increase oxytocin that is free and can be done any time any where, is metta or loving kindness meditation.
Search metta or loving kindness meditation scripts on google and do it. Even if you don't feel anything you are rewiring your brain to make it more positive and if you do stick with it you will over time become a more positive and caring individual