NRV is Nutrient Reference Values - indicate the daily amount of nutrients required for good health, as well as a safe intake of nutrients. That is something else than the flour gluten/protein level, but NRV will increase as the gluten/protein increase.
Yes, the higher the gluten is - the better result with pizza dough.
I use Denti flour with parameters:
12.8% - 13% gluten
leavening time: 24 h
strenght: W 390-410
extensibility: P/L 0.50-0.65
I'm very satisfied with the results. I do not know if it is reachable in China, probably not so popular as Caputo. If you search for a flour take a look at the W factor (strength) and the water absorption - they are some kind of universal measures so it is easier to compare flours.http://www.molinodenti.it/en/flour/pizza/