What MoveFocus(AccessibleNavigation, Boolean, Int32) and FindNext(AccessibleNode?, AccessibleNavigation, Boolean, Int32) look for.
public enum AccessibleNavigation
ISO 32000-2 §14.8.2.5 (reading order), Spec #33 viewer capability 8.
kind:method, kind:property, kind:ctor. Press Esc to clear.ControlThe next element of an IAccessibleElementProvider, in its focus order.ElementThe next node in reading order, whatever its role.FigureThe next figure.HeadingThe next heading, optionally of one level.LandmarkThe next landmark: a section or a note.LinkThe next link.ListThe next list.PageThe first node of the next page (of the previous page, backwards).TableThe next table.