What do you mean, exactly? If you want to put multiple quote tags in a post, just press the Quote button in the appropriate place (e.g., a new line). You seem to have managed it in the post you just made, so I'm confused as to what you're asking for.
If you mean quoting a post that has already quoted another post, then they will be nested because that's the only logical way to do it.
If you want even more control then just cut and paste and move the BBCode quote tags around as much as you might like.
Humor is the second most subjective thing on the planet
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Brevity is the soul of wit and obscenity is its downfall
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Good Night And Good Luck - Read You Soon
If you are replying the thread is laid out in reverse chronological order below, if you want to selectively quote highlight the bit you want and then hit quote and it quotes it correctly but only that section, not the whole post. Rather handy.
Humor is the second most subjective thing on the planet
------------------------------------------------------------
Brevity is the soul of wit and obscenity is its downfall
--------------------------------------------------------
Good Night And Good Luck - Read You Soon