doubt on stored procedure

CREATE TABLE [dbo].[STS_ADDRESS_BOOK](
         [AB_NAME] [varchar](100),
         [AB_EMAIL] [varchar](100),
         [AB_FAX] [varchar](100),
         [AB_ID] int NOT NULL IDENTITY(1,1) CONSTRAINT primarykey PRIMARY KEY) 	   


-----------------------------------------------------------------------------
sp,


GO
IF OBJECT_ID ('dbo.selectAddressBookInformation1')IS NOT NULL
DROP PROC  selectAddressBookInformation1
GO

CREATE PROC selectAddressBookInformation1 @columnvalue varchar(100),
@searchword varchar(100)
AS

exec ('select* from STS_ADDRESS_BOOK where CONTAINS('+@columnvalue+','+@searchword+')')

-----------------------------------------------------------------------------
this  command executed successfully.But the problem is on executing the sp

using, 
-----------------------------------------------------------------------------
exec selectAddressBookInformation1 @columnvalue=[AB_NAME], @searchword='hari'