A higher nic level will give you a better TH, and adding VG will cut it down a bit, but you can get a different kind of TH by adding certain flavors, menthol, cinnamon, peppery flavors, and there are 'artificial' TH liquids as Variable mentioned, but straight up, nic and heat are what give you the TH. Someone correct me if I am wrong, but this is what I've learned in here.