@sir fortoz.. sir salamat, saka pede paki explain in-layman terms.. hinde ko maintindihan
Most speakers for general use these days are available @8 ohms that's the reason why I mentioned that 55W RMS as your baseline figure.
Those days amps are rated RMS so with speakers which changed to Peak, PMPO etc. Now to get a matching speaker for your amp rating @8 ohms, double that which is 110W to get rid of that RMS (approx. conversion). That is only the minimum rating of speaker as specified on your manual.
As per Sir V's advice for safety reason due to higher volume levels or sudden drive of sound level, you need to at leas get a speaker of almost double that rating which in this case 220W. From those figures, there are no speakers on that range so get 200W or 250W.
Note: This is also my basis on previous posts that when the amp rating is in RMS, just multiply by 4 and you can get the approx. rating for the speakers needed to be safe.
Of course if budget is tight, you can always buy the lower rating but when it's busted you end up paying more. If this is the case, don't push too much volume for the amp.