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

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