Sandy sits next to 3 phonetic neighbors — Andy, Randy, and Sandi are the closest matches by sound. Most share Sandy's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"defender of men"
"bright raven"
"Sun; throne - from Old Persian Kurush meaning one who bestows care"
"rosemary (when short for Rosemary)"
"rough clearing or rough woodland clearing"
"bright raven"
Similar sound: These names share phonetic patterns with Sandy — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Greek origins, giving them the same cultural heritage as Sandy.
Rhythm: Sandy is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.