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

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

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