Multiple "conditional seperators"

Hi I have a problem in a Multiplayer Map.
I want an event happen after a unit is in a special area and a special unit is selected

So the Trigger is
C1 Objects in area player 1 - 1 object
C2 Object selectet (multiplayer) - Player 1 - a unit
OR
C4 Objects in area player 2 - 1 object
C5 Object selectet (multiplayer) - Player 2 - a unit
OR
C6 Objects in area player 3 - 1 object
C7 Object selectet (multiplayer) - Player 3 - a unit
OR
C8 Objects in area player 4 - 1 object
C9 Object selectet (multiplayer) - Player 4 - a unit

Effect 1 Display Instruction “Hello. Blablabla”

The result is, that the Instruction will be displayed just, if player 1 selects the unit, not if any other player is doing it. What I’m doing wrong?

I know I can create 4 different triggers for each player, but it’s very unsatisfying and will result quickly in thousands of triggers.

Not sure if this will work, but here is an idea. You could split it into three triggers. The first trigger has as it’s conditions, If Object in area player 1, OR Object in area player 2, etc, to cover all the objects. Then, as the effect, it sets a variable to 1. Your second trigger then checks all of the object selected, and sets a different variable to 1. Your 3rd trigger then checks if both variables are 1, and displays the message.