Psalm 139:3 (ESV)

3 You search out my path and my lying down and are acquainted with all my ways.

Wherever I go, or wherever I lay down my head to rest, God knows it all. In the original text, a verb is used that first of all means to sift, as one does with grain. The chaff is separated from the kernel. That is why a fitting translation here would be to vet, or to probe. The Lord sees deep (inside).

He removes the shell from us, which seems to (want to) hide our inner core of what keeps us occupied. For him, we are an open book.