I would be very careful when working with the Loa. They don't appreciate dabblers and non-initiates. Voodoo dolls are not a part of the *religion* of Voodoo - the initiatory religion of Voodoo. Also, Voodoo is not a system of magic. It is a common mistake, though.
I'm confused about the words/sentences part of your question. Are you looking for spoken charms and incantations?