How to search Special character in SQL SERVER

How can i search special character in column

  Create table test

  (

       ID int,

       ProductName varchar(100)

  )

  Insert into test values (1,'hey%boss')

  Insert into test values (1,'helloboss')

  Insert into test values (1,'hiboss')

  Select * From test

  Where ProductName like '%[%]%'

  Select * From test

  Where ProductName like '%\%%' ESCAPE '\'