I have google this alot, but unfortunatilty found no working solution.
I know its a bad technique, but I need to send user its password by email.
I have manage
Short answer is that you don't 'decrypt' the password (because it's not encrypted - it's hashed).
The long answer is that you shouldn't send the user their password by email, or any other way. If the user has forgotten their password, you should send them a password reset email, and allow them to change their password on your website.
Laravel has most of this functionality built in (see the Laravel documentation - I'm not going to replicate it all here. Also available for versions 4.2 and 5.0 of Laravel).
For further reading, check out this 'blogoverflow' post: Why passwords should be hashed.