Find Next (Ctrl + K) within an editor will search for the next occurrence of text previoulys searched for in Eclipse’s regular search dialog (when the dialog is closed). If the inline search was used for the last search, the text searched for through the inline search dialog should be used, but this does not currently happen. Ditto for Find Previous (Ctrl + Shift + K)
https://marketplace.eclipse.org/comment/5014#comment-5014