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