How can I remove these labels completely?

I love those jars (and the yogurt is tasty) I let mine sit in hot soapy water for as long as possible, then use Goo Gone. It takes some work but I don't mind.

Try soaking in cold water. If that does not work, spray with WD40 and let sit a while. This should remove the glue.

Old fashioned idea here, cover the label with butter and let set, then clean off. If that doesn't work then use a chemicle called GOO GONE. Let it soak on . Might have to do a second time, then use a metal scrub pad to get it all off with hot water. If you have sensitive skin, wear vynel gloves. It can be harsh on some people's hands.

I've done a lot of these. You can peel the plastic label off with an occasional assist my a razor blade. Add another product to remove the adhesive -- mineral spirits paint thinner.

I soak them in hot water with a little Dawn overnight. Peal off what I can in the morning. Use Goo Gone to remove any residue. Then run through dishwasher. :)

Really hot water does it for me.

rub any oil on the residue,that should loosen enough to be able to scrap and wash off the residue

If the label doesn't take the water when you soak it, try to rip off the top of the label, then soak it. Some labels don't let the water get in until the top layer is off.