If a newly entered item on the Mac is showing up on the iPad, that means syncing is working. If syncing is working, it carries all of your data to the new device; there's no provision for only syncing some of your data. As you are a new OmniFocus for iPad user, I think a likely answer is that you are not using it correctly and are hiding most of your data from view. Here's an easy test: tap on the magnifying glass at the top of the screen, and type in a word from the name of one of your "missing" projects or actions. My suspicion is that you'll see some matches. At that point, you've established that the data is on your iPad, and you just aren't viewing it. If you tap the "house" icon in the sidebar, just below the Inbox counter, then tap the left side of the Projects button, it should show you all of your projects, subject to the current view settings. Tap the eyeball icon (next to the magnifying glass) and you can choose which items are displayed. If you set that to "All" you should see everything in your database.