Perhaps you should try some spelling variations:
"4x400 metres relay" » "4x400 mestres relay", "4x400 metros relay", "4x400 metres rela", "4x400 metres delay", "4x400 metres reay"
"4x400 metres dela" » "4x400 mestres dela", "4x400 metros dela", "4x400 metres della", "4x400 metres delia", "4x400 metres adela"
"4x400 muestreos pelay" » "4x400 muestreo pelay", "4x400 muestreados pelay", "4x400 nuestros pelay", "4x400 muestreos pelayo", "4x400 muestreos pelaya", "4x400 muestreos play"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("4x400 metres relay") OR ("4x400 metres dela"))) OR ("4x400 muestreos pelay"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"4x400 metres relay\") OR (\"4x400 metres dela\"))) OR (\"4x400 muestreos pelay\"))*".
• Removing quotes may allow a broader search: (((( 4x400 metres relay ) OR ( 4x400 metres dela ))) OR ( 4x400 muestreos pelay ))*.