Perhaps you should try some spelling variations:
"synchronised swimming" » "synchronized swimming", "synchronize swimming"
"synchronising swimming" » "synchronizing swimming", "synchronisations swimming"
"synchronising stemming" » "synchronizing stemming", "synchronisations stemming", "synchronising streaming", "synchronising steering", "synchronising flemming"
"synchronism swimming" » "synchronize swimming", "synchronized swimming"

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 ((("synchronising swimming") or ("synchronising stemming"))))) or ("synchronism swimming"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("synchronised swimming") OR ((("synchronising swimming") OR ("synchronising stemming"))))) OR ("synchronism swimming")).
• Removing quotes may allow a broader search: (((( synchronised swimming ) or ((( synchronising swimming ) or ( synchronising stemming ))))) or ( synchronism swimming )).
• Adding a wildcard symbol may retrieve word variants: (((("synchronised swimming") or ((("synchronising swimming") or ("synchronising stemming"))))) or ("synchronism swimming"))*.