Miracles happen only when you do not force them

Why is happiness such a strange thing? Why is it the joy is gone every time you stop to think about it? I guess the miracles happen only when you do not force them to. Like pleasant surprises or when love occurs. These split second joys like solving complex math equations or a smile from a nice girl or having a hard long laugh with the best of friends grow less fantastic in time. Materialistic thing just doesn't do it for me no more neither, sure new stuff is nice, expensive stuff even nicer but these things only seem to be overly magnificent for days or weeks before they lose their value in creating joy. I'm on a mental journey, I'm heading for the place where I can be happy for a long time in a row. Does anyone really know where that is?