Use the "Advanced Search", the link, VERY top right, below the search field box.
In the new window, in Keywords field: Maroubra
Additional Options: Find Posts: 6 months And Newer
That'll cut down the shop ad clutter.
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Or try:
On the webpage: Forum: Sydney - After Report
Below the Thread Display Options section, below the Show Threads, on the right hand side, SMALL link to "Search Forum". In the pop up, type Mascot with the Show Threads radio button selected (the buttons below the field).
That will also cut down on the shop ad clutter.
Once you find some specific shop names, then search on those names. Sequential process, but believe me, worth the time.