As it turns out, basically nothing makes people happy. Happiness for each person is pretty fixed at their own individual level.
We can temporarily influence our happiness for days/weeks/months with externalities but without fail we always return to our baseline. You can more permanently stabilize your happiness by being part of a community, avoiding drugs & alcohol, caring for your body, and being in a loving relationship.
This guy is pretty smart and spent most of his professional career researching and proving just that.