Set it to On Demand and check your results. It should perform DNS lookups for IP hosts as needed and will display names where resolvable.
Now, NTA won't show you a simple hostname like 'www.google.com', since the Netflow table refers to the resolution of the specific IP to which the client is connecting. You'll likely see lots of CDN providers (akamai and the like).
If the IP resolves to a nice, simple name then you're good.
For example, here's a quick scrape of some talkers:
