I just purchased new content for the Cyber Monday Sale.  When I went to go into the content management, I cannot figure out how to select which specific sources to give the other players access to.  I bought some books that they should not be able to see, like the DMG, and three campaign books.  Is the content sharing all or nothing?  How do I only share certain books with the other players?  

Do you have a Master Tier subscription?  That is required for content sharing. 
if you do have a Master sub and you have turned on content sharing, you should see a “content management” button to the right of the “disable content sharing” button near the top of the campaign page. 

Yes, I have the Master Tier subscription, and the content management button only appears to let me share all of the content.  I was under the impression that I would be able to select which specific texts I would like to share.  I do not want the other players to have access to all of the texts I own (particularly the campaign book for the campaign we are playing and the DMG) but I do want them to have access to the Players handbook and Xanathar's Guide to Everything.  

I just tried setting up a campaign, and that one lets me manage the specific texts I am sharing.  It looks like the reason that I can't control the specific texts is because I am not the DM for that campaign.

I think only the DM can adjust which sources are shared.

Houligan is correct.  I missed that you weren't the DM.  So you will need to ask the DM to turn off access to those things you don't want the players to have access to.