Do you have the same problem like this?.
Then use the unlock button(Ctrl+Alt+L ) on top left corner in 2D plan drawing window.
Choose Edit-> Select all/Select all at all levels then by hold shift and click on objects(like compass,particular wall or furniture) to toggle selection. Then press Delete button to delete those that you don't want.
Else please give more explanation or can you attach your work file.?
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