Hapiness is defined differently by different people. Some will be happy by buying trinkets or experiences. Some by having a happy family. Some by being remembered by others. Some by helping others in need. If you aren't the person that wants to buy their hapiness, then no amount of money will help.
Then again, it helps a shitton in all of the above, up to a point.
I think it's better said as "money enables happiness". If you have enough money that your needs are met, then you are free to pursue whatever makes you happy.