No wonder I didn't understand. "like" is "xi huan" not "xi hua." And "hair" (like head hair) is "t?ufa", not "duo fang" (I don't think I've even heard duo fang. What are the tones?) You also forgot the possessive particle "de".
我喜欢你的头发.
wǒ xǐhuan nǐ de t?ufa.
I like your hair.