Low sperm?

So my husband went on eBay and bought this test to check his sperm and it came back low. Our insurance doesn't cover fertility treatments or seman analysis which I was completely fine with because of course I never wanted him to feel bad or feel like he was the reason we are still ttc after 17 months. My question is is this test legit? Is there hope or Is there anything we can do to improve his count? We have 3 beautiful children already but would love 1 more if possible. Any advice would be greatly appreciated :)