Perhaps you should try some spelling variations:
"synchronised swimming" » "synchronism swimming", "synchronising swimming", "synchronised stemming"
"synchronize swimming" » "synchronize stemming"
"synchronized swimming" » "synchronized stemming"
"synchronismd swimming" » "synchronismd stemming", "synchronism swimming", "synchronising 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 ("synchronize swimming"))) or ((("synchronized swimming") OR ("synchronismd swimming"))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("synchronised swimming") OR ("synchronize swimming"))) OR ((("synchronized swimming") OR ("synchronismd swimming")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"synchronised swimming\") or (\"synchronize swimming\"))) or (((\"synchronized swimming\") OR (\"synchronismd swimming\"))))".
• Removing quotes may allow a broader search: (((( synchronised swimming ) or ( synchronize swimming ))) or ((( synchronized swimming ) OR ( synchronismd swimming )))).
• Adding a wildcard symbol may retrieve word variants: (((("synchronised swimming") or ("synchronize swimming"))) or ((("synchronized swimming") OR ("synchronismd swimming"))))*.