Odra sits next to 3 phonetic neighbors — Audra, Ondra, and Indra are the closest matches by sound. Most share Odra's Polish-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"from the Odra River; noble strength"
"shining light, bright torch"
"Wonder, miracle, something marvelous"
"elf wisdom"
"world-mighty"
"silky, like floss"
"born in spring, of spring"
"possibly from Clara, meaning bright and clear"
"strong, healthy, vigorous"
"of the Vandals"
"Yahweh saves"
"mountain"
"bright, shining one (via Eleanor/Lenora)"
"wagon maker, wagoneer, carter"
Similar sound: These names share phonetic patterns with Odra — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Slavic origins, giving them the same cultural heritage as Odra.
Rhythm: Odra is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.