Hi @Andreas_Vlcek,
Could you please tell me if the User is the Person type and the Skills is the Choice type allowing multi select?
If the User is Person type and the Skills are Choice type allwoing multi select, please add a Gallery and set the Items property as below:
Filter(List,"2" in Skills.Value)
This is for all users have skill 2.
Filter(List,Concatenate("2",",","3" ) in Concat(Skills,Value,","))
This is for all users have skill 2 AND 3.
I would suggest you use the ComboBox to list all the skills, and then you could filter Gallery based on ComboBox selected skills:
Filter(List,Concat(ComboBox13.SelectedItems,Value,",") in Concat(Skills,Value,","))