It is a bit tedious to answer the question "this was where the traffic was sourced from, and this is where it was destined for" because of how NTA displays the data currently.
1) You can click on any of the interfaces listed in the NetFlow Sources View on the NTA Summary page and you can see where traffic is flowing from that interfaces' perspective. There is no way I know of to get a quick "end to end" view of a flow. I do have a feature request for adding this ability on to the Atlas map here: https://thwack.solarwinds.com/ideas/3621
2) you can also do a search by endpoint IP, or port in the search bar on the NTA Summary Page.
3) You can build your own pages that show exactly the traffic, time frame, or interface that you want to see, but again these do not display how the traffic is flowing end to end.
HTH...
