How did the Polynesians discover islands like Hawaii'i, that are thousands of kilometers away from other islands?

by northwards

They must have traveled this distance regularly in order to discover tiny islands in the middle of vast open ocean. Would this have been a deliberate attempt to discover new land, or would it have happened during fishing expeditions or something similar?

Searocksandtrees

Hi, you may be interested in this long-form answer by /u/thefairyguineapig in

There are huge gaps between islands in the Pacific, what methods did the Polynesians/Islanders use to discover them and to stay on course in a trip between two islands they already knew existed? Do we know how many/what percentage were lost at sea?

Note that there are links to a few more threads at the bottom. Also, if you have followup questions, given that that post has been archived, just ask here & tag the relevant username to notify them.

YourWelcomeOrMine

This has been asked many times before https://www.reddit.com/r/AskHistorians/comments/3l89i6/how_did_hawaiian_natives_get_to_hawaii_in_the/