More data is usually available. It takes time or money, but you can get more data.
But you’re probably not using all the data you’ve already got.
I’m guessing what you meant was, “I wish I had more certainty.”
And that, unfortunately, isn’t available.
If it’s worth the work you put into it and the change you seek to make, it’s worth dancing with the uncertainty. Reassurance isn’t going to come from more data–that’s a stall.
Forward motion is the best way to make things better.