The best solution would be to get a teacher so that he can see exactly where the problem is. Unless someone sees up close how you play, it will be difficult to determine why you don't play as good as you want to.
The other really obvious thing is to keep practicing. Play the song over and over again. See which parts of the song give you more trouble and play them alone over and over again.
Also, see which technical parts of the song you have trouble with. Like you said you cannot do vibratos well. The way to improve them is to take some simple exercises for vibrato and practice them before you jump in a song that uses them. When you have developed the technique, take the part of the song with the vibratos and practice that alone.