Doll lips gets searched a lot, and it shows up in clinic ads, but when you go looking for an actual method behind the name, there isn't one.
What you find instead is a mix. One clinic uses it for cherry-style fullness in the centre plus a defined Cupid's bow. Another uses doll-like language for cherry lips in general. And "Russian doll lips" often points at something else again: Russian-style height.
So if you tell an injector you want doll lips, you're really asking them to guess which of those you mean.
What tends to work better:
Here's a page on the doll lips look and where the name comes from, with the sources listed. It's an illustration and a glossary entry, not a prediction, and a provider has to see your lips before saying what suits you.
Sofia R., LookPrep