Perhaps you should try some spelling variations:
"synchronism swimming" » "synchronized swimming", "synchronism stemming"
"synchronize swimming" » "synchronize stemming", "synchronized swimming", "synchronizing swimming"
"synchronising stepping" » "synchronizing stepping", "synchronisations stepping", "synchronising stopping", "synchronising shopping", "synchronising shipping"
"synchronised steering" » "synchronized steering"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("synchronism swimming") or ((("synchronising stepping") or ("synchronised steering"))))) or ("synchronize swimming"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("synchronism swimming") OR ((("synchronising stepping") OR ("synchronised steering"))))) OR ("synchronize swimming")).
• Removing quotes may allow a broader search: (((( synchronism swimming ) or ((( synchronising stepping ) or ( synchronised steering ))))) or ( synchronize swimming )).
• Adding a wildcard symbol may retrieve word variants: (((("synchronism swimming") or ((("synchronising stepping") or ("synchronised steering"))))) or ("synchronize swimming"))*.