"Cé leis é seo?" is an Irish phrase that translates to "Whose is this?"
A response to "Cé leis é seo?" would typically include the owner of the object. For example:
"Is liomsa é." ("It is mine.")
"Is le Seán é." ("It belongs to Seán.")
"Níl a fhios agam." ("I don't know.")
