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

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

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