Diluting is one option, but don't go more than 5-10% water or you'll start to notice loss of flavor.
Nhaler has some KR808 clear cartos that actually handle thick juices (including Boba's and other ave juices) quite well. They're a similar design to the CE3's. I'm guessing you have a 510 device, so you'd need a 510-808 adapter to use them, but they're worth a look