My bf won't do anything extra with me...

My SO and I have been together over a year and he has never fingered me or went down on me. Don't get me wrong, I still get off. But that stuff would be nice. I've talked to him about trying to give me oral pleasure a time or two or try touching me down there and he says "alright alright I will, just don't expect me to try right away." Well we had that talk months ago and he's yet to try anything new like that. He's been with women before and he's done it before but he said his ex didn't like it so he just completely doesn't think about it. I think there's more to it than that though and he won't tell me. I don't want to make him uncomfortable, I just want to understand. How can I open him up about all this stuff? I've tried talking to him about it before and it just made him angry and upset.