Re: no thick smoke
You're shisha might have dryed a bit, if it is so it can't provide as much smoke as it used to, unless increasing the heat it gets, but this can lead to burn the shisha.
You should try adding some honey and glyerin to the shisha and let it absorb it for a couple of hours.
The honey is for the same purpose as molasses in the shisha and glycerin just increases the amount of smoke.
Be careful, don't put to much of these things on the shisha, if I'm right a half teaspoonful of both seems to be enough for like 100gramm of dry shisha, however others might prove me wrong.