It is solved. Thank you, again.

The following might be flawed, but it is my best memory. [Some times, I set a meaningful config. value, or something else with persistence; and forget it.]
Open dolphin. In the left column, there are two lists: "places" and "devices".
In "places", select "Network". In the right column, there will appear items like: "Network", "Samba Shares", and "Add Network Folder".
Select "Add Network Folder", and then click the magnifier icon with the label "Find". A new text field will appear.
In the new text field, enter something like "fish://username@hostname", and type the Enter key.
My memory is fuzzy. Some where I was given a chance to enter a name to call that network folder. I did so.
The name I gave then appeared in the left column under places.