Perhaps you should try some spelling variations:
"synchronized swimming" » "synchronized stemming", "synchronismd swimming", "synchronizingd swimming"
"synchronising swimming" » "synchronising stemming", "synchronizing swimming", "synchronism swimming"
"synchronisations swimming" » "synchronisations stemming", "synchronisation swimming", "synchronizations swimming", "synchronization swimming"
"synchronize swimming" » "synchronize stemming", "synchronism swimming", "synchronizing swimming"

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

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