Ejaculate increase??

Ok, I’ve read a million & 1 times that men with small amounts of ejaculate doesn’t mean a man is infertile. I’ve seen that men with small amounts can be more fertile than those with a large amounts. But I can’t help but think my husbands small amount of nut is the reason we’re not conceiving. I mean, we watch porn often & I’ve seen normal men with these big amounts they release.. I’ve seen some with amounts that weren’t much too & my husbands amount is way less than that. We went for Sperm count testing but were unsuccessful being that he barely had any in the cup. I’m no Sperm expert but I know that’s not enough he’s producing to get me pregnant. He know it as well. What should I do? 😫 And are there any things he can do & take that’ll boost the amount of ejaculate he release? He does have 2 kids from a previous relationship. One isn’t biologically his (the oldest) & we just found that out last year so that mean he only MADE one son & he’s 5 years old. Maybe he’s having 2nd hand infertility or something? I don’t know what more to do, I’ve been to the doctor & have meds to help aide me but I can’t be the reason by myself these past 3 years. And he doesn’t have any STDs, I know those lead to small amounts of ejaculate & infertility. He has before, previous relationship again. But I doubt that’s the reason. Please help, I want this to be our year!