Can someone help me?

Google ad chocies lets you customize which ads you see allowing you to get ads that relate to things you're interested in. I'm okay with seeing ads, ads can provide revenue to those who own a website which is good thing. However I have one problem: sometimes I get ads containing content that I don't want to see.

Due to experiences I've had, I'm sensitive to anything relating or containing blood and gore. In fact this is why I stopped watching tv and started using netflix, because I get full control over what I watch. Sometimes on the internet I see ads which advertise gorey video games or horror movies and it really scares me. I want to know if there's a way to customize ad choices so that you don't see ads containing certain things. I've searched more than once before and I still can't figure out how to do this.