Excuse my english (native german speaker).

On page 11 "exploring" the rules state, that the player is not amused with the first dice-roll. But instead of exerting to reroll one die, the player decides to take another action...

But Questing needs 2 actions and you have only 3 actions in one turn...?

Or do I misunderstand something?

Yup, rules are correct. You're making a slight confusion on two different actions:

- Adventuring: while you resolve this action, you draw one card from the deck matching the color gem on the hex you are in. This action requires two action slots, so, unless very special circumstances, you'll never be able to resolve an adventure action more than once / round

- Exploring: it's a different action. Some cards in the game are "quest cards" (most of them are in the green deck). When you draw a quest, that card instructs you to go to a specific hex on the board and perform there an explore action. When you resolve the explore action, you roll terrain dice and check the results on the card. This action uses only one of your three action slots / round, so that in the very same round you can explore up to three times the same hex

Hope this helps

Ah.

So I would take 2 actions to draw a card on an Exploration (Adventure) gem from the expl. deck.

It is possible that the card instruct me to go to a certain hex to explore. That will cost 1 action then.

Right?

Yup, right!