Welcome to SoM! :)
I'm not really understanding what you mean.
If you mean that you could try to use magic to make somebody see some things positively then that most likely won't work.
If you want somebody to see positively about things, be there for them, care for them, respect them, being a friend to somebody can be a good way for them to see positive about things.
Giving good advice, inspiring words, and being cheerful with/around them could be other ways to help them to see positively.
Anyone can have the 'power' to give positive thoughts to the other person, but those can be done by actions and words, not really by your mind (if you was talking about that and I didn't notice, or I'm not on topic and that's not really was you was asking.)
If you have any more questions, feel free to ask.