In House of Cards, there are three important terms that define different ways in which cards cycle: renew, replenish, and refresh.
To renew a hand is simply discard your hand and draw back up to your current hand maximum. This occurs in situations which represent a dramatic change that throws everyone off-kilter: when a Shuffle occurs, for instance, everyone has the option to renew their hand, becoming part of the plot twist that accompanies the Shuffle if they do. This is the simplest and least powerful form of hand management, if for no other reason than that it causes lots of cards to be “churned”, but it is the baseline from which the others extend.
By comparison, to replenish your hand means you keep the cards that you have and draw back up to your maximum. The advantage over renewal is that powerful cards remaining in hand aren’t discarded. It also doesn’t press quite so aggressively toward another Shuffle, in that fewer cards are being pulled from the deck. A number of Lesser and Greater Powers include replenishing one’s hand as a part of using them, almost always at the expiration of the power – a notable exception being the Dreamthief ability possessed by denizens of Beyond.
When you refresh your hand, you can selectively discard and draw, making it the most potent option, which occurs rarely. One of the Fool’s possible Greater Powers allows the Fool to refresh his or her hand instead of renewing it; a Shuffle should be a reasonably uncommon event in itself, which reins in the scope of this power, which thematically represents the Fool’s ability to keep walking the circular road of life with some sense of continuity.