HEY.. i know some of you know this technique but there are some that does not know this simple thing...
first create a room in any dungeon you like(trial forest for example)
second finish it fast..
third quit the game when the bar is full(refer to the image below)
forth make another room..
then boom.. you'll get the items that you got in the dungeon
but you wont have the chance to pick to those 4 treasure boxes...
i know this is a noob thread but this is the only way i can help those who are'nt strong though
hope i helped..
press thanks if i helped