you can declare a global var in a form and assign it and hide the form

-- exec proc sp_Find_in_Proc('searchstring")

CREATE proc sp_Find_in_Proc

@SeachString varchar(255) = NULL

AS

IF  @SeachString is Null

   Begin

    Print 'Missing Parameter @SeachString!'

    return

   end

DECLARE @Pattern as varchar(255)

SELECT @Pattern = '%"' + @SeachString + '%'

Print...