acer aspire v5 561g

Hi, i've installed Yosemite on my laptop (Acer aspire v5 561G) without lots of broblem, but now audio, ethernet and wifi aren't working... so i can't do much. Hardware details: http://store.acer.com/store/aceramer/en_US/pd/ThemeID.35703000/productID.295337500 Please help me, what can i...