Hi,
I have found the root cause. There were existing network in between SSG140 and ASA5506 that is using a same network with internal ASA5506 network 192.168.2.x (note that between SSG140 and ASA5506 is a microwave network with multiple hops). That is why SSG140 internal network could not reach 192.168.2.x as its already exist in current network.
My plan is to create IPSEC Site-To-Site VPN between SSG140 and ASA. Once the VPN is established, from SSG140 I can reach 150.150.0.0/16 am I right? I will try it tomorrow and will share you the result. Thank you for your advise.