One might say this is one of the reasons Dumbledore wanted Slughorn on his side.
Though, I’m sure Snape could have made it too, and if Voldemort ordered him to make some, I don’t see him getting out of it.
The in-story reason why Voldemort doesn’t seek help in this way is pride. He believes he is superior, and thus, should be capable of killing Harry unassisted.
“Listen, Severus, I want you to brew me a cauldron of Felix Felicis, but I can’t have the other Death Eaters finding out about it…” No, he could never admit to anyone, neither Snape nor himself, that he needed such a handicap to kill a teenager.
He Who Must Be Named Voldemort made that potion with Harry’s blood - that sounded really complex. Voldemort should’ve been using it* and distributing it to Death Eaters.
(edit) *Felix Felicis
You mean the “get your body back after dying with a horcrux” potion? Yeah, I’m sure that would really come in handy for lots of Death Eaters.
Yes that one, oops meant Felix Felicis though