One ring to rule them all.
One ring to find them.
One ring to bring them all.
And in the darkness bind them.
In what way does the one ring find anything? Do we have some reference, besides this poem, that Sauron could use the ring to know where all other ring wearers were?
The other 3 lines seem true. The one ring was about control and certainly had the ability to rule and control other ring wearers. But, not sure about finding them.
Three rings for elven kings under the sky
Seven for the dwarf lords in their halls of stone
Nine for mortal men doomed to die
One for the dark lord on his dark throne
In the land of Mordor where shadows lie.
One ring to rule them all... Etc
I'm no expert, but I've always interpreted it as the One Ring being semi-sentient in and of itself, and it wanting to find all the other rings of power and consume them in the darkness. And also of the One Ring's ability to find the people and creatures that will enable it to do so (IE Smeagol).