Sia sits next to 3 phonetic neighbors — Mia, Gia, and Thea are the closest matches by sound. Most share Sia's Scandinavian cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"victory (short for Sigrid)"
"beautiful, beloved"
"rival, industrious"
"from the hay field"
"follower of Christ"
"youthful goddess, keeper of immortality"
"short form of Helena or Magdalena"
"eternal ruler, ever mighty"
"narrow strait or channel"
"boomerang (curved throwing stick)"
"free woman, free person"
"grace, favor"
"princess, noble lady"
"navigator of the sea"
"pure, virginal"
"beautiful"
"grace, favor"
"sun ray"
"mounted warrior, horseman"
"divine wisdom"
Similar sound: These names share phonetic patterns with Sia — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Norse origins, giving them the same cultural heritage as Sia.
Rhythm: Sia is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.