From tämä. Related to Finnish tänne. This etymology is incomplete. You can help Wiktionary by elaborating on the origins of this term.
tänna
- to here, hither
- this way
- Zajceva, N. G., Mullonen, M. I. (2007) “сюда”, in Uz’ venä-vepsläine vajehnik / Novyj russko-vepsskij slovarʹ [New Russian–Veps Dictionary][1], Petrozavodsk: Periodika