It's a bit hard to explain and in the end I can't give much more of an answer than "that's the way it is", but think of "Drem Yol Lok" as an idiom. It seemingly has no literal meaning, but as an idiom it means "greetings". If you want to go more literally: "sky" and "fire" are two of the most important elements to a dragon. The "Peace" before them indicates good intentions or wellbeing.

Another way to think of it is that "Drem Yol Lok" is a "Shout". "Force Balance Push" has no literal meaning, but together it produces unrelenting force. Sort of in the same way, "Peace Fire Sky" has no literal meaning but comes together form a greeting. Hope this helps!

I would have never thought of that.You're wisdom of the Way of The Voice never ceases to impress me,Paarthurnax.

Lok Thu'um.