The first thing to remember about writing a book is that you must be interested in the thing you're writing about. Writing just because people online have suggested one of your topics isn't enough; if I tried that, I'd get bored pretty quickly and move on to something else. Write about what you love. Write about what you know. And, if I may suggest, either write in your native language or work really hard on improving your English before trying to write in it.
"Now everyone was giving her that kind of look UFOlogists get when they suddenly say, 'Hey, if you shade your eyes you can see it is just a flock of geese after all.'"
"You can't erase icing."
"I can't believe it doesn't work! I found it on the internet, man!"