Need help splitting the eye brow

Hey, I want to split the eye brow (and other sections of this model) however I do not know a clean way to split it as the split tool is not precise enough, I would apriciate any recommendations.

Hey, I want to split the eye brow (and other sections of this model) however I do not know a clean way to split it as the split tool is not precise enough, I would apriciate any recommendations.