Board Game Arena

Can someone explain how these work?
There are 5 tokens on the board.
When a player obtains 2 science of the same kind the rules state they get to pick one of the 5 progress tokens from the board.
However in a game I am playing, my opponent was forced to take from the box. Not the board.
Why would this happen?

She would have won the game if allowed to take from the board since she would have taken "law" and thus had 6 different science

Thanks

That's a wonder effect.
One of the wonders allows you to immediately take a token from the BOX (not from the 5 available)

I see what happened now. Science was buried to build the wonder. Thanks