Yes, money can't buy certain things including happiness. What it does buy are material things and services. Even services have a material aspect in their delivery. What money cannot buy are particular states of the mind such as happiness, peace and contentment.
One must of course have sufficient money that allows buying the goods and services which facilitate such states of mind up to an extent. Facilitate, but never really purchase or cause directly. Beyond that limit, money actually becomes counterproductive.
The paradox of money is that it's often taken as an end in itself rather than the means to an end. But the human reality doesn't work that way. To use a term from economics, even money has a marginal utility value beyond which it starts acquiring negative worth instead of positive.
Rich people are always bothered about their bank balance, how to preserve and enhance it, how not to lose it. That constant worry and the ensuing endless effort running around after more results not in happiness, but the precise opposite. It's literally tantalizing like the Greek mythical figure Tantalus himself, where the water disappears as soon as one tries to drink it.
That explains the paradox why poor people are often happier than the rich. They neither have anything to lose, nor really the means to acquire more. They learn to make peace with that fact. As long as they have something to eat and a shelter over their heads, they have nothing more to worry about. In that worry free state, even simple things delight them in a way that our own jaded thinking never can. You may not believe this, but I've actually seen happy homeless people who live on a pavement.