。
She searched high and low for the ring.
Literal
She [topic-は] eyes [object-を] plate [like-のようにして] ring [object-を] searched.
目を皿のようにして ('making one's eyes like plates') is an idiom meaning 'to search thoroughly with wide-open eyes.' It's a vivid image of extreme attentiveness. 指輪を探した is 'searched for the ring.'