Having sexual trouble with new girlfriend

My girlfriend and I get along great, we have an amazing relationship, but when it comes down to it getting her to orgasm is impossible. She is a virgin. I've had two girlfriends that lasted over a year each and had no problem getting them screaming,...

but my normal technique is not working.
My girlfriend and I are very comfortable with eachother so I talk to her and ask her what feels better because im stumped. Normally teasing her getting her a little wet then wetting my fingers and rubbing her clit just doesn't do anything. She says she likes it better when I actually finger her, but I lived in there for like 25minutes once, had two fingers in there and was rubbing the sensative area in the vagina, (idont know the name... but it feels different then every other place when your fingering her, you like curl your fingers and you feel it about an inch in), but getting a light moan is the best I've gotten.
I feel bad because she does whatever I want her to do and of course im satisfied, this is just frustrating because before her I took pride in my ability, now im just angry.

does she do it herself? because sometimes if she doesnt do it then it might not work aswell... I know how she feels though... I had a time where I had like no pleasure from it... but she has to kinda work as well like kinda push herself?!... I would probably tease her for about half an hour, dont go near her clit at all, make her want you to an extreme. start feeling her legs up, go futher up with her clothes still on, kiss her neck, move your hands all over her, nibble her ear, feel her up under her clothes, go down there but DO NOT touch her clit yet!!... keep teasing her .. when she cant take anymore slowly go to it, rub it a bit, then come away, and keep repeating it, then do your technique.. you should hopefully get something outta that =) x hope I helped