Perhaps you should try some spelling variations:
"synchronised swimming" » "synchronism swimming", "synchronize swimming", "synchronising swimming", "synchronised stemming"
"synchronised streaming" » "synchronism streaming", "synchronize streaming", "synchronising streaming"
"synchronised treating" » "synchronism treating", "synchronize treating", "synchronising treating", "synchronised creating", "synchronised heating", "synchronised relating"
"synchronized swimming" » "synchronized stemming"

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (((("synchronised swimming") OR ("synchronized swimming"))) OR ((("synchronised streaming") OR ("synchronised treating"))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"synchronised swimming\") OR (\"synchronized swimming\"))) or (((\"synchronised streaming\") or (\"synchronised treating\"))))~".
• Removing quotes may allow a broader search: (((( synchronised swimming ) OR ( synchronized swimming ))) or ((( synchronised streaming ) or ( synchronised treating ))))~.
• Adding a wildcard symbol may retrieve word variants: (((("synchronised swimming") OR ("synchronized swimming"))) or ((("synchronised streaming") or ("synchronised treating"))))*.