Ianna sits next to 4 phonetic neighbors — Iona, Iana, and Hanna are the closest matches by sound. Most share Ianna's Scottish cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"God is gracious"
"strong spear"
"corn, maize"
"elm tree"
"strength of the spear"
"nickname form of Adelaide, Addison, Adeline"
"fair, blessed, holy"
"from brandy, the distilled spirit (Dutch etymology)"
"the beloved, darling"
"tree bower, shaded alcove"
"male deer, hart"
"combination of light and grace"
"little meadow, dear clearing"
"uproar, disturbance"
"modern elaboration of Zora"
"grace, divine goodwill"
"land where rye is grown"
"light, radiance, beams of light"
"peace; from Ireland"
"woodland clearing (Locc's meadow)"
"breath, wind (original meaning)"
Similar sound: These names share phonetic patterns with Ianna — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Hebrew via Scottish Gaelic origins, giving them the same cultural heritage as Ianna.
Rhythm: Ianna is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.