Place it at the end of a failed explanation or awkward reveal, then follow it with a Vine Boom for impact, or lead in with an Anime Wow before it takes over the scene.
關於此聲音
This clip is a single drawn-out vocal fahhh, stretched over about two seconds as one breathy, exasperated exclamation with no other words or music. It lands as funny, dismissive and fed up, the sound of someone giving up on explaining and letting the sigh do the talking instead.