There are 2 simple questions
1. a. I haven't slept for good time
b. I haven't slept good time.
c. I haven't slept well.
Which sounds natural?
2. Russell harnesses a wild sense of invention to bring us closer to ourselves.
To bring us closer to ourvelves? what does that mean? It's not clear.
"I didn't get enough sleep."
I would say there's a difference between "I haven't slept well" and "I didn't get enough sleep". It's possible to sleep badly for many hours, but you could sleep very well for only 2 or 3 hours and say the latter.
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.