That won’t help either. How does fasting make you happy? It doesn’t - unless you believe in magic.
Praying, though, definitely helps. You see what you are looking for. If you’re not searching for something, you always miss it.
If you pray for positivity, you are in fact searching for it, and so you will find it.
Giving charity will not help either if your attitude isn’t right. There are a lot of things that are supposed to make us happy but some times they don’t, because there’s something wrong with OURSELVES.