I believe all of the RTW products prohibit re-entry into a continent (except for transit), and ICN and BOM are both in Asia, so you want a product that allows 2 entries into Asia. Maybe the Circle Indian Ocean product would allow this (it is like a GE but excludes Europe and NA). You could fly ICN-HKG-BOM-HKG-MEL on any of the RTW products but not in the sequence that you want. There is no way around this except by buying point to point tickets (at much higher cost, generally). You could fly ICN-HKG-DPS and buy separate ticket DPS-MEL-DPS for example (that might be cheap as it is a high volume leisure route) and continue DPS-HKG-BOM on the RTW ticket (and this might make the RTW ticket cheaper if you no longer need Australia).