[scribus] font issues

[Adrienne Carmack]

I am having problems with the appearance of my exported pdf. Although
it looked great in Scribus, it does not look the same at all when
viewed as a pdf on a Mac or PC or when viewed on an iPad or iPhone.

I did use a variety of fonts, but they are all true type or open type.

One of them is a simple bold font that is pretty standard, and on the
Mac/PC, it just shows up as an empty space. But it shows up fine on
the iPad or iPhone.

Some of the fancier fonts I tried to use look completely different on
the different devices.

Is there a way to fix the appearance?
Is there a written primer on how fonts work in Scribus somewhere?

Many thanks for this and the great answers I got to my previous questions!
Adrienne