Q:

What is: Yellow Flour?

We were told that yellow flour (Italian) can be added to normal white flour to make a good crispy pizza dough?

What is this yellow flour?

A:

The yellow flour you are referring to is most likely durum wheat semolina, which is yellow in color and is often used in making pasta, breads, and pizza dough.
As noted in some of the comments, semolina can come from different grains and other types of wheat.
Please see this  link  for more information about semolina.

