For me the best practice regarding Try Catch is to select a general exception like System.Exception and not a particular one as yours.
In the catch field you can use Log message or Write line activity instead of Message box because Log message will not pause your program in case of any errors. In the text field of Log message you can write something like that:
hey @Manohar1
if my selector is not match then this action go to catch block right?
that action is not goinig to catch block and that i want to do if selector not found then go to catch
Hey @Manohar1
you are not understand what i wan to do is simple if selector is not found then go to catch block. that i want to do norma try catch block.