On the "today", "7 days" or any other search result, all tasks are shown that meet the search criteria, for example - are due today, regardless of their indent level.
We've chosen this display as both other alternatives could be confusing:
1. If we would only display sub-tasks with their indent levels - then you would see on your today list tasks intended under other tasks that they don't really belong to and may even be from different projects.
2. If we would only display sub-tasks under their parent tasks - then we would have to show the parent task even if it won't meet the search criteria, so you would have to expand every task that may not even be due today, to find one or more sub-tasks that may be due today.
The current solution allows you to see all tasks due today, but if one of those tasks is a parent task - you can expand it to see what sub-tasks it contains. You see some tasks twice only if both the sub-tasks and the parent meet the search criteria.
Of course, we always try to improve the app and if you'd like to suggest a better solution, you're welcome to do so and we would appreciate it.