sales talk vs publicity

sales talk and publicity both are nouns.

Word	Noun	Adjective	Verb	Adverb
sales talk	Yes	No	No	No
publicity	Yes	No	No	No

As nouns, publicity is a hypernym of sales talk; that is, publicity is a word with a broader meaning than sales talk:

sales talk: promotion by means of an argument and demonstration
publicity: a message issued in behalf of some product or cause or idea or person or institution

Other hypernyms of sales talk include packaging, promo, promotion, promotional material.

sales talk (noun)	publicity (noun)
promotion by means of an argument and demonstration	the quality of being open to public view
	a message issued in behalf of some product or cause or idea or person or institution