Kitti1 I looked into this a while ago and made a post about it here healthunlocked.com/thyroidu... It's worth checking out the links within that post too.
It's K1 that aids blood clotting, K2 aids in sending calcium where it is supposed to go (basically!).
However, you might have read a post of mine when I said that for some reason, when I do a fingerprick test. I've found that if I leave off my D3/K2 combo supplement for a few days then my blood tends to flow better. That's just a personal anecdote, it's not to say that it's the same for everyone.
Whether K2 does actually have some effect on blood clotting seems to be debatable. As you already have thick blood I think you should do some research to satisfy yourself.
As a cautionary tale, I'm not one to tell anyone what they should and shouldn't do, so please don't think this is a a lecture , but my late father was a lifelong smoker. His arteries furred up (one of the effects smoking can have apparently), and eventually this narrowing of the arteries meant it was difficult for blood to flow normally. He slowed down a lot and had trouble with his legs. He passed away in his sleep, post mortem was carried out and it was explained to my mother that they thought a small clot couldn't get through the narrowed arteries and blood flow to the brain or heart was lost causing his death. As you already have thick blood, have a think