Strange problem when transfering songs

Hi Everyone,

I have a very strange problem when i transfer songs to my iphone.

When i transfering songs maually (dragging them from ITunes music library to my iphone) i can see that they are in my iphone (at "On This iPhone"),
but when im looking in my iphone (in the music library) im seeing only 70-80% of the songs.

And the strange thing is that i can see them if im searching them!

Please help.

Thank you!