Clasping Nausicaa's knees was deemed too risky by Odysseus, since Nausicaa might have reacted poorly to his touch. Instead he talks to her, and admires her beauty. Nausicaa senses that Odysseus means no harm, and decides to help him out (Odysseus later tells the story of his journey to King Alcinous and Queen Arete--Nausicaa's parents who help him get back home to Ithaca).
