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