This is currently only something that can be accomplished with AppleScript. However, it sounds like from your description that each objective starts a section. The problem with this as far as just copying the objectives, is that if you copy a parent (through normal copy/paste method), all child rows are copied with it. However, depending on what you're doing with this list, you can just collapse the sections to hide all the questions.
To copy just the questions out, you can use a script that selects the row level they're on, something like:
Code:
tell front document of application "OmniOutliner Professional"
set stylename to text returned of (display dialog "Enter name of style to look for:" default answer "")
select (every row whose (name of named style of styles is "find") or (name of named style of level styles contains "find"))
end tell