hola everyone, i'm thinking of escritura a mystery book. does anyone have good ideas for a plot?

Look to horror cine and fantasía fiction for good ideas. Try to avoid cliches and don't finish with a cliffhanger unless you're a REALLY good writer.

How about this:
After the disappearance of their mother, two sisters and a brother embark on a journey to their homeland of Peru to find out what caused their mother's sudden disconnection to them (because they get calls and letters from her a lot). While there, they get clues and get closer to the truth: their mother was an escaped sex slave who had three illegitimate children during th traffic, and after around 2 decades, the "pimp", who was still pissed off at losing one of his prostitutes, finally found her and planned on killing her if she didn't return to the trade. Now in addition to finding their hiding mother, they also have to find out who this man is and stop him before he tries to kill their mother.