My current board suddenly hid my cards

[Liraz]

For some reason my current board suddenly doesn't show my cards from this week. I can see they're still there - under the name of each list you can see the number of cards on that list (see image). The other boards (like the one from last week and the one I already made for the next) are showing the cards on their lists. So what happened? How can I restore the cards for the current board and see them again? Hope someone can help.
Thanks in advance!

[Liraz]

Well, I solved it!  I can't see any option to delete the question so for the benefit of others who might have the same problem: It was a filter. I removed it by pressing the Filter button (next to the Automation button). Can't remember messing with it (let alone noticing it) until now but there you go :)