Here is the full list of all 9 Detective Grimoire achievements. It takes around 2-3 hours to unlock all of the achievements on Windows.
Complete the game
Draw a cute ghost in your notebook
Full suspicion on the culprit, none on anyone else
Examine all the Boggy merchandise
Read the letters on Remington's desk
Get inside the tent
Complete the game 100%
Examine the crime scene
Finish speaking to the Little Girl