If you travel so frequent i suggest you to take annual plan. Hassle free. But take note on the maximum no. of days per trip, usually up to max 90 days per trip. Most insurance company will exclude war countries so if you did not travel there it's fine.
my vacation in melborne will be 9days, can i prolong the travel insurance coverage to 10days? as the price is same as 9days
Can issue up to 10 days.

arrange transfer of patient from oversea to local if they find the medical expenses it too much compare to local, with the certify from the physician that patient is stabile for transfer, then will be back to local medical expenses which is 50k. Correct of i m wrong
I believe you refer to Medical Evacuation? It means here that they will transfer you to a more adequate hospital (overseas or locally) if the hospital you admitted is not capable to treat you. Should a follow up treatment need to be done after you return home, then you are able to do so within 30 days with max limit 50k.

only cover robbery & pickpocket , with police report