[AngelicaDeAlquezar]

"Alguien", with no accent.

I can't grammatically explain why, but I would say:

- Queremos encontrar a alguien que pueda ayudarnos.

Or

- Queremos encontrar una persona que pueda ayudarnos.

It seems "alguien" is more specific than "una persona" ("alguien" doesn't accept an indefinite article).