We’ve written up a few new tips on using OmniFocus:
How to Exclude Tags in a Custom Perspective shows how, on Mac and iOS, to set up a custom perspective that excludes tags that you don’t want to see.
How to Search Your Entire Database (on the Mac) details how to change the search scope so you can search the current perspective, remaining items, or everything.
How To Assign a Project to an Inbox Item Using Drag and Drop (on the Mac) tells you about the preference that shows your Inbox in the Projects tab, and explains how to use spring-loaded drag and drop to move items from Inbox to individual projects.
It’s also worth remembering that our support site has a bunch of articles — for all our apps — and it’s searchable.