Detachment is not indifference. it is the prerequisite for effective involvement. Often what we think is best for others is distorted by our attachments to our opinions. We want others to be happy in the way we think they should be happy. It is only when we want nothing for ourselves that we are able to see clearly into others needs and understand how to serve them.
Without going outside, you may know the whole world, without looking through the window, you may see the ways of heaven. The farther you go, the less you know. Thus the sage knows without traveling; he sees without looking; he works without doing.
The desire of your vital being is towards work. And the vital being won't find any interest in yoga so long as you do not have any experience of the higher and fuller life that is in yoga. As long as this experience is not there, the vital being will not find any interest.