"In Doriath, even reading in Sindarin is an uncommon skill. You might gain better results by leaving such texts among the Noldor, or at least the Khazad or tbe Sindar of the havens."
In speech, it might not be so obvious, but via thought-sharing, it's clear that when he refers to the Khazad, it's the same people that Luthien calls the Naugrim.
"The cities of the Khazad lie along these eastern mountains, although they share their exact location only reluctantly with outsiders, and this map does not list them. The great forest in the center is Doriath, the kingdom in which we reside, and the smaller woods to the east is Nam Elmoth, the territory of Eol. He, along with the inhabitants of the Havens of Falas under Lord Cirdan- centered around Brithombar at the mouth of the Brithon and Eglarest at the mouth of the Nenning - and the scattered Nandor and Laiquendi of the south are direct vassals under King Thingol.
"To the North and east lie the fortress-towns of the Feanorians, although they are mostly now in ruins besides Himring. The Feanorians serve their lords, the sons of Feanor, who in turn obey their eldest brother Maedhros and supposedly above him the Noldorin High King Fingon, but the kinslayers are give scant loyalty to any of the house of Fingolfin. On the northwest side sit the territories of the House of Fingolfin; Hithlum, and its sub territories of Mithrim, Dor Lomin, and Nevrast, which were under the control of Fingolfin, Fingon, and Turgon. Turgon and his people left their homes to found Gondolin, and thus Nevrast is largely empty, while Fingolfin's death leaves both territories directly under Fingon. Here also dwell the house of Hador, the greatest surviving Edain kingdom.
"In Dorthonian once dwelled the house of Beor under King Finrod, but the coming of the shadow in the battle of sudden flame left their forces in ruin and their kingdom occupied; Their lord yet lived when last I saw him, but it has been many hard years under the shadow since and we have heard no word if any survive. To the southwest of Doriath lies Nargathrond, the hidden city of King Finrod, and from that fortress he controls the surrounding plains and hills of western Beleriand.
"Further north than the territories this map covers is Angband, the central Fortress of The Enemy, and his soldiers roam the plains of the north. His chief servant, Gorthaur, rules out of the Island of Werewolves, which fortress he seized from Finrod; it guards one of the few paths to the north, and should be given wide berth."