In the new ribbon interface it's sometimes difficult to find/remember where some tools are located.
Ribbon search is an easy way to find tools or dialogs across multiple tabs and workflows of the ribbon. In the Search Ribbon field on the top-right corner of the ribbon, enter the partial or full name of the tool or dialog and you will get a list of results with the given name in a window below the Search field.
Hovering the mouse pointer over any of the listed tools expands the details of the tool and where you can find it in the ribbon.
See also this short video about that functionality:
More information about this in MicroStation CONNECT Edition Help under the title Ribbon Search.