Translation of "In ihrem inneren" in English

Denken sie denn nicht in ihrem Inneren (darüber) nach?
Do they not reflect on themselves?
Tanzil v1

Denken sie denn in ihrem Inneren nicht darüber nach?
Do they not think deeply (in their ownselves) about themselves (how Allah created them from nothing, and similarly He will resurrect them)?
Tanzil v1

Sie halten in ihrem Inneren geheim, was sie dir nicht offenlegen.
They conceal within themselves what they do not reveal to you.
Tanzil v1

Der in ihrem Inneren ansteigende Druck spannt die umgebende Zellwand.
In an isotonic solution, water flows into the cell at the same rate it flows out.
Wikipedia v1.0