What other airlines should I search to capture the gaps in Qantas award searches?

As many of the airlines available are not shown on the Qantas FF website are there any tips on any other sites I can use to see flight paths and check availability? It’s doing my head in…
Wanting to fly Sydney - Asia - London or Rome - Asia - Sydney.

If you are after Oneworld, a combination of American Airlines, British Airways and Qantas should cover most if not all gaps.