I also believe that ALG-FOC is some kind of special program behind it. Fuzhou is the last thing I would input when I am looking for fares. But also be careful, when inputing multiple cities to multiple cities in Google Flights they will not show all fares of all pairs, so it is not as efficient as you think. About the India one it is just a remnant of the NH open jaw party ex USA-Asia-Canada in Feb. You can see a lot of deals never really go away, or sometimes when the airlines trying to cover up the mess they dont do a great job at covering all tracks.