as far as i can tell from
http://service.us.panasonic.com/OPERMANPDF/SAHT730.PDF page 32 of your manual you only have red and white (L/R) audio inputs as well as zero hdmi, zero optical and zero coax. it also looks like the set doesnt support ARC (audio return channel).
basically... this means that you can only get left/right sound out of any additional equipment you hook up to your home theater in a box set and you can get surround sound only out of items which were included in the set such as the dvd/br player which comes with it.
to be frank though.. most of the content you could possibly pull from the television is going to be stereo only. even if you were streaming netflix on a smart television i do believe most netflix is still stereo only sound so having 5.1 support would do little.
something like this
http://www.amazon.com/Digital-Converter-Optical-TOSLink-Coaxial/dp/B00BVT4M30/ref=sr_1_6?s=electronics&ie=UTF8&qid=1405445243&sr=1-6&keywords=optical+to+rca can take an optical signal and convert it to left/right channel audio. however, as i said previously you will only get 2 channel audio unless of course your reciever supports faking SS with one of the various sound modes available nowdays.
if you want true surround sound support you would need a different receiver (however, since your tv audio is likely to be stereo only i dont see how this would help you unless you intend to connect other sources such as game systems, different dvd players, a computer, etceter).