Early in the movie Star Wars: A New Hope (1977), at the Mos Eisley Spaceport cantina, while looking to hire a charter for Alderaan, Obi-Wan Kenobi is introduced to Chewbacca by BoShek. Near the bar, the old hermit and the towering Wookie start a murmured conversation. They talked in the Wookiee language that, by that time, Luke didn't understand.
Regarding the mentioned scene, here a couple of Canon references:
From the Star Wars A New Hope novelization we can read:
In the course of the conversation the old man had occasion to gesture in Luke's direction. Once the huge anthropoid stared directly at Luke and let out a horrifying howling laugh.
Disgruntled by the role he was evidently playing in the discussion, Luke turned away and pretended to ignore the whole conversation. He might be acting unfairly toward the creature, but he doubted that spine-quaking laugh was meant in gentle good-fellowship.
From the Star Wars A New Hope movie Script (4th draft) we can read:
Ben speaks to the Wookiee, pointing to Luke several times during his conversation and the huge creature suddenly lets out a horrifying laugh. Luke is more than a little bit disconcerted and pretends not to hear the conversation between Ben and the giant Wookiee.
I assume that words and phrases like "to the Alderaan system", "no questions asked", "Yoda?", etc. could have been part of the conversation but I wonder if there is any Canon/Legend reference of the content of the aforementioned conversation between Obi-Wan and Chewie.