for fear of stating the obvious, these wont cure your issue but will help a bit.
As a better option, but a bit more expensive buy a dehumidifier.
My car is bone dry, but leave my portable dehumid* in it over night every now and again after a valet and it will pull 1/2 a pint of more out.
they are lethal for damp in garages and a great bit of kit to have in general.
all makes and models sub £80 much of muchness, so grab a bargain and stop damp, mould and mildew collecting in your car mate?
But the Thor Mar bags do work, but are passive and just allow the moisture to be pulled in by the desiccant granules.
Seriously consider a dehumidfier you will not regret it - peanuts to run!
