How can I strengthen ejaculation without increasing the time I spend having sex?!

How can I strengthen ejaculation without increasing the time I spend having sex?

I have almost never had a problem with orgasming quickly, but, I would like to "shoot" further and release more semen. All that Ive found is either to have less sex to have more ejaculate, or to do exercises that may actually increase the time I spend having sex.
My girlfriend is much less into sex then me, and if it starts taking me longer, Im afraid we will have less sex.
Do the exercises lengthen the time of intercourse for all males, and is there anything that will make me produce more semen on a constant basis?

1 month ago
With my girlfriend being less into sex then me, I often times find a hand job to be the most satisfing way to be pleased when she doesnt want me to have genital sex. She generally is not interested in in forplay unless she is already in the mood, and really I just want to shoot further because it would help my own satisfaction.

Since you don't come too quickly, don't masturbate between your sex sessions and have her build you up 1-2 times before actually letting yourself come.