Why does the Strategy Guide does not have any tutorials? (and instead tutorials have cheats?)
(I have skipped few tutorials and can't find 'em aigain)

Which tutorials are you looking for?

As far as I know the strategy guide is supposed to only show the "intended" way of doing things for challenges. Which is a shame if needing to recheck a tutorial for any reason. I have the idea stuck on my head that there's a section for tutorials within the game's menu but I may be mistaken, will have to recheck that later.

I skipped the shadow mode. And I skipped how to set a point that shows how many people look at that point.
(and may be I skipped somothing else)

Yeah it's pretty easy to skip tutorials.

Short summary would be something like:

Shadow Mode:
By pressing SHIFT you can assign different actions for different characters. Just remember to press SHIFT between each character so that they won't immediately just do the thing you're trying to assign them. After you've assigned all the tasks you want, pressing - if my memory serves me - ENTER makes them all execute the assigned tasks simultaneously.

Marker:
By holding RMB (right mouse button) you can set the marker on the field where you want, and it will make a line from the enemy only when it sees the marker. Rather useful tool when arriving to new area and not being sure if you saw all the enemies in there.

That's pretty much what the tutorials tell you I think, I can look further if needed. If you already know all those and just wondering if there is tutorial somewhere, hopefully someone else finds that somewhat useful.


EDIT:
Ok checked if there are tutorials stored in-game, and there truly are, even if not that user friendly way. At least I didn't see another way.
Basically while on a mission, press B to open up your journal with mission objectives and such, from there Tutorials tab is the second from the right, next to the Badges.

The less than optimal thing with that, is that you must have seen the tutorials in that level before those shows up in there. It isn't enough if you've seen those once, but you must have seen those in that level while you're playing the mission. So if you are starting a new mission to collect extra badges, the tutorials will appear in the Tutorial tab after you've collected the tutorial scroll again.

Apologies for the wall of text.

Thanks!