I have a European driving license which is completely written in Czech (see photos below). Can I use it for driving in the U.S. (I will go to Hawaii for 3 weeks), or do I have to obtain another document where the information is written in English?
As Karlson pointed out already, the Hawaiian law does not require you to have an international drivers license. Additionally, your drivers license is rather obvious in terms of clarity to understand what it means.
However, I would still highly recommend you to get a IDL. You might run into a policeman who simply wants the documents written in English. Since IDLs are normally easy, cheap and fast to get, it should be a good thing to have to minimize trouble when getting in conflict with the law.
Also, it should be another point of concern where you get your car from. If you rent a car, you might want to check with your car rental company if they want you to present an IDL.