Here is the full list of all 32 Sherlock Holmes and The Hound of The Baskervilles achievements.
For collecting all the achievements
For completing the game in hard mode
Finishing 10 HO in a row in less than 3 minutes each
For completing the tutorial
For not skipping any dialogs
For completing the game
Completing all puzzles without skipping
All HO without hints
For finding 300 objects
For using materialization 3 times
For using telekinesis 3 times
For finding 200 objects
Solve 1 puzzle in more than 10 minutes
Finishing 10 puzzles in a row without skipping
For using the speed ability 3 times
Find 10 objects in 10 seconds
Finishing 10 HO in a row without a hint
Finishing 1 HO without missing clicks
For finding 100 objects
Finishing 1 HO in more than 10 minutes
Finishing 5 puzzles in a row without skipping
For using the perception 3 times
1 HO in less than 1 minute
Finishing 1 HO with less than 10 wrong clicks
Finishing 5 HO in a row without a hint
Finishing 5 HO in a row in less than 3 minutes each
Finishing 3 HO in a row in less than 3 minutes each
Finishing 3 HO in a row without a hint
Finishing 3 puzzles in a row without skipping
For using the power ability 3 times
Solve 1 puzzle in less than 1 minute
Find 3 objects in 3 seconds