It happens to me couple times. You have 10 card library. For some how, you only got 4 or 5 of 10 cards for multiple turns (5+). You never saw the rest of 6 cards. But keep repeatedly draw the same set of 4 cards.
Until you cast a big draw cards spell, like draw 7 cards, you break the curse.
It is extremely annoying me when you have 3 creature cards in your set. But you never draw a single creature in like 6 turns.
If you have zero creatures in hand to start and have three creatures in your deck, you have a 13% chance to not draw any creatures for an additional four rounds. That’s not exactly astronomical odds - it’ll happen pretty frequently.
Multiple little draw cards, like Discovery or Notion Rain, also help you find what you’re looking for. I never play without a considerable amount of draw or fetch in my deck (unless I’m playing, like, 8 creatures, say for Training Grounds, or some reason).