Something doled out in miserly amounts is provided in “dribs and drabs.” A drib is a smaller relative of a dribble. Nobody seems to be sure what a drab is in this sense, except that it’s a tiny bit larger than a drib.

Since the origin of the phrase is obscure, people try to substitute a more familiar word for the unusual word “drib” by writing “drips and drabs.” But that’s not the traditional formula.