unable to focus app on mac

we are trying to focus on an app in mac using tile but that does not seem to work. also in documentation it is mentioned to use app.focus first
can some use please provide the code snipped and documentation is not clear

my code:
App.focus("Adobe Acrobat")

Documentation:

 not yet possible, to identify a running app by part of the title of it’s frontmost window. If you want to use a window title to match the application, use App.focus() before, to get a valid App object.