Hey Idaho, I'll be glad to address your question. YES, you can train yourself to have multiple MONSTER anal orgasms, at least in solo sex with toys. I can't always get them when I'm getting dicked by a bud. Here are my suggestions:
1. Get a good-quality prostate massage vibrator toy and start using it. I suggest one with both inside and outside vibrating heads, like the LELO HUGO. Good chance you won't get any orgasms the first couple of times, but you should get a really nice high and sense of well-being. Prostate play connects directly to your brain releasing large quantities of pleasure-giving chemicals. You can bump up the effect by smoking some 420 before you start. I recommend NOT using poppers. You'll start getting your first orgasms at some point; they'll likely be very mild compared to what you're gonna learn to do, and they may cause you to ejaculate. This is something you can learn to control.
2. Once you've got your prostate's attention, he will swell up with eagerness when you just start playing around your hole with your fingers; he knows what he wants. At some point start trying other toys. Vibrating butt plugs are great, but they may take another learning curve because they're not specifically designed to bend over and sit right on your prostate. Short thick dildos can be really good. They may require a little work to properly stimulate the prostate, but if you can get a good orgasm started, it's AWESOME to cum with that fat little dick filling your rectum and stretching your hole.
3. Always give yourself PLENTY of time for asshole work. No stress, no hurry. Before you start, smoke some 420 and take a good hot shower cleaning yourself inside and out. Very dim indirect works best for me. Soft music is fine. RELAX. You're here to have fun. Keep taking a toke here and there during your play; the higher you get, the more profound your experience will be. Best to do your play at night right before going to sleep.
4. It helps me if I ejaculate sometime earlier in the day either by jacking off or fucking a bud. That takes the edge off, which is a good thing because then I won't easily blow a load when I start getting into my ass. I'll be able to give myself anal orgasm after anal orgasm after anal orgasm without having to worry about my damn dick wanting to get in on the action; he just gets in the way during ass play. Of course if your sharing ass play with another bottom bud, you'll want your dicks hard so at some point in your play you'll be able to fuck the bejeezus out of each other.
5. Seems like the charge on most of the vibrating toys lasts a little over an hour. So if you have a couple of toys charged and ready, you're good for over two hours. If you're using a non-vibrating dildo, then no problem.
6. EXPERIMENT. Find what works best for you. And have fun.