The hints that have been seen will not appear again..
Unless you go to this path to delete the corresponding file of the hint((if it's Windows):
C:\Users\%UserName%\AppData\Local\Ghosts_and_Japes\resources\hint
or....read the "strings_en.txt" file....
But hey! That might be a SPOILER, so.. plz try not to do that.
(All of the above text is translated using a translator, hopefully they don't look weird lol)