How to get the Liana Jungle award

Ok, I've found a decent list, here are the secret achievements. Note that all of the structures must be on the map at once to gain the award (you can't build 14, demolish one, then build another).

Hot Dogs Fan: Build 15 hot dog stands
Simple Solution fan: Build 15 cabins
Trifles Fan: Build 15 gift shops
Spa Salons Fan: Build 10 sunny centers
Mega Party Goer: Build 10 disco
Aristocrat: Build 3 golf clubs
Casinos Fan: Build 5 crystal casinos
Altitude Lover: Build 2 galaxy restaurants
We Remember about the Defender: Build 2 gold defenders
Amusement Park: Build 2 observation wheels
Great Pyramids: Build 3 pyramids
Lord of Excitement: Build 3 pearl casinos
Master of Bowling: Build 3 Bowling clubs
Following the Montgolfier Brothers: Build 3 Ballon launch platforms
The Sun Only: Have all power generated by solar stations, remove all windmills

Go to the social button on the bottom right of the screen. Hit the friends tab, you will be taken to their island. Above three of their facilities you will see a cleaning brush. Tap each of those to receive money.