On this page of the Disco Elysium guide, you will find a detailed walkthrough of the Investigate Doomed Commercial Area quest.
Your objective in the Investigate Doomed Commercial Area quest in Disco Elysium is to find out whether the abandoned commercial building behind the bookstore is indeed cursed.
During the conversation with the owner of the bookstore, you will find out that the building connected to the bookstore is cursed. Plainsance will ask you to investigate the case, find evidence of a supernatural force (Malignant entity) and report it.
Go into the basement of the abandoned building and head into the room where the Ice Bear Fridge stands. Approach the stove. Examine the device, then try to pass the Physical Instrument skill check. You will hear a woman's voice coming from inside the shaft.
Then try to pass the Shivers skill check - you will hear a woman's voice again. This time she will invite you upstairs, to the second floor.
The door to the room behind the heavy iron blind is open – you can go inside. You'll meet Novelty Dicemaker, a woman who makes dice for role-playing games. Talk to her about the causes of bankruptcy of companies that had their headquarters in this building.
After talking to Novelty Dicemaker, go back to the bookstore owner and tell her what you've been able to find out about the alleged curse. During this conversation, you can point out the true cause of all tenants of that building going bankrupt, or lie and say that the curse really exists.