That? Oh, that's canned hyena laughs.
9 seconds sound clip from Scooby-Doo, Where Are You! - A Clue for Scooby Doo (S1E2).
You can hear this line at 00:07:30.228 in the Blu-ray version of the episode.
Quote context
[...]
- I guess it's up to you, Velma.
- It's up to all of us. Now, march!
- Wow! Like, this place is furnished in early Halloween.
- It's obvious. She practices witchcraft.
- Hey, look at these. What zoinky labels. Ear of a newt?
- That? Oh, that's canned hyena laughs.
- Velma, who do I know with long, skinny hands?
- Zoinks!
[...]