You have to pick up and read all the different items in the game, which all look like an orange handheld thing that makes a large holoscreen when you pick it up except for the 3 flat screen "journals". There is a secret datapad in each chapter which looks just like the newspapers but in their long stories have a 1/5, 2/5 and such at the top of them. You only need one of the newspapers per chapter and don't need to read each individual one(although i did read each tab on the newspaper, not sure if its required), but newspapers are everywhere and easy to find.
Journals: Chapter 2, the one Dorian has you read to find the coordinates on the table in his lab.
Chapter 2, The one with the instructions for making Tea in the greenhouse tent.
Chapter 4, It's on the right side of the bed in the loft and tells you Alice likes cheeseburgers.
Secret datapads:
Chapter 1, it's on the back of the couch facing the exit door in the living room.
Chapter 3, after the VR training, there is a couch behind the elevator with 2 datapads on it, one is the secret one.
......ill update this later as i forgot to remember the locations of the other 4.