Cockroaches!!? abet?? I live in Greece and since yesterday I have see two huge...

I live in Greece and since yesterday I have see two huge cockroaches in my house. And I'm terrified by them. My gran kill both of them but I want to know what I can do to prevent cockroaches from entering my house. Please help..!!
Use boric acid powder. Sprinkle around windows lower than cabinets, stove and refrigerators, and out side of the house, but make sure no pets or children come contained by contact with it, it is poison. You can use a baby nasal syringe. Don't depart from food out, because roaches like to eat food. Don't move off any dirty dishes out for too long. Keep trash off the floor. I don't know if they have it within Greece, but their is this stuff called Chinese chalk that roaches will die when coming in contact near it.
You shouldn't kill them, they're completely tasty deep fried.

Don't start out any food or garbage out for them.
Keep the house clean.
Set up a corner contained by the yard for them so they won't have to come into the house.
Make sure you put food out for them contained by the same place at the same time every hours of daylight or they'll come into the house looking for it.
Answers:    Im a bug man for 6 years now. Best method is to pest proof your house. Add Door sweeps to doors that own light from outside coming in from underneath and trademark pipes that enter your house. Then make sure you turn light rotten at night and have correct blinds over windows because almost all bugs are attracted to restrained. Then thirdly lay down a barrer of pesticide from your local hardware store on the exterior and interior around all the cracks and crevices in your home. DONT JUST SPRAY ALL BASEBOARDS. Roaches dont live on your baseboards. Lastly pest baptism. Know your pest! Make sure you know what your up against and get the right pesticide for the right pest. If it were a German Cockroach I would report to you to seek professional help because even we hold difficultly as pest professionals in getting rid of this pest.
keep your house clean and spray so assault around the house Super clean your home, spray for bugs every 11 days 4 times ..go outside and spray for bugs and they are gone.