Used to refer vaguely to things without specifying them, similar to 'this and that' or 'such and such' in English. Often used when the speaker does not want to or cannot be specific.
For such and such reasons, I'll take the day off today.
He said he does this and that kind of work.
Rare kanji form; not commonly used.
Reduplication of これ (this), used to indicate multiple unspecified items.