Hisoka might be able to rig some of the smaller, more standard doors — these would contain cleaning supplies for the most part, and mundane necessities. With the more difficult, smaller doors and an excess of brute force, he'll discover a pair of walkie talkies (lacking in batteries), a survival knife and a box of matches. Try not to kill someone too quickly.

There also appears to be flavor packets for the "space goo". They come in roast beef, cherry and birthday cake. Enjoy...?