ITunes: How do I get music purchased on my phone onto my computer library?

Here's my problem: I purchased a few songs from iTunes ON MY PHONE, therefore, that music is not on my computer iTunes library - just my phone. I want all of the music that is on my phone to be on my computer, BUT, I DON'T want all of the music that is on my computer library to be on my phone library. (The computer is a 2010 Macbook, and my phone is an iPhone 5).

I want that music that's on my phone to be on my computer BECAUSE I want to use that music from my phone for iMovie - which of course if you've used iMovie you know you can only select music from your iTunes Library on your computer, and those certain songs aren't on my computer, they're just on my phone, etc you get the jist.

SO can someone please tell me JUST how to get all of the music that's on my phone onto my computer iTunes library? AGAIN - I wanna make this as clear as possible - I DO NOT want music from my computer to go onto my phone (I DON'T want it vise versa). For example, I have every single Beatles song on my computer, but I don't want all of those beatles songs on my phone because of the enormous space it takes up and I don't listen to them on my phone. Hopefully you get what I mean.

On your computer go the iTunes Store. On the right side of the screen there's an area called quick links. One of the links says "purchased", click on that. On the next screen in the upper right is a button that says not on this computer. Click that. It will show you all songs your account has purchased that aren't on that computer. You can download them again without paying for them

With regards to controlling what music is or is not synced there's check box next to each item in your library. Un-click the songs you don't want on your iPhone. When the iPhone is connected to the computer, click on the iPhone icon (upper right with version 11 of iTunes), in the menu of options you see click on "sync checked" - then only those songs that are checked in the library go on to the iPhone.

"How do I get music purchased on my phone onto my computer library?"

Open iTunes on the computer.
At the top menu bar, click either "Store" or "Account" (depending on the version), and then "Sign in".
Use the same Apple ID that you used on the iPhone.
At the top menu, choose "Store".
At the right frame, choose "Purchased".
Download whatever is missing.

Your smoothest use of iTunes will be to avoid buying music on the phone, and just buy it on the computer. Then when you sync, all the Mac purchased music will copy to the iPhone. When friends text you to buy some song, just copy the song name and save it as a note. Later use that note for purchase from the computer.

"I DON'T want all of the music that is on my computer library to be on my phone library."

That is a separate issue. When syncing to the iPhone, you should start by making a playlist on the computer just for the iPhone. Then you can sync that playlist only to the iPhone. See the link below.

If you create a Playlist, you can add to that, and never worry about having a bunch of checkmarks to remember. If you had 200 songs in the "iPhone Playlist" and later added another 50 songs, the original 200 songs will NOT get duplicated. You will always get all the songs in the playlist copied to the phone.