Going to move this over to the Gen. Hardware section, as that's where you'll get the help for this.

nunzmon
triplight makes a unit that will keep your voltage stable
look them up on the web!  I use one on all my pc's 

i joined the website  but  i didn't understand anything can u be specified ? 

Might want to also consider an Uninterrupted Power Supply (UPS) Battery. They give you a battery for when power goes out, help during brown outs so you do not loose your work, and take the noise out of the power stream, as well as stabilize the power for the computer. I would never build a system without one. Here's a link to what Amazon has but these are readily available most everywhere. http://www.amazon.com/s/?...;ref=pd_sl_r16mmh7h_ee

many high end UPS ( unintrupted power supply ) will have voltage regulations build in.
 
just look for a UPS with voltage regulations, shipping to lybia will cost an arm and leg so find one at local store if possible.
 
essentially it will use the battery to make up for the voltage when it dips below, and hopefully cut it off when its above.
 
If the power is really that bad, i would buy a enterprise one , it will not die because of over voltage. it will simply shut off the input power, use its battery, after a few seconds it will try to use wall power again.
dont get one that is rated near your PC wattage, get one with atlease 20% head room above your pc wattage.
 
triplight is used alot in data centers.