Speedtree UE4 wind on single leaves

Hi all

i have a problem with the wind and the leaves (single meshes).

i can’t understand how single leaves can move by WIND in Unreal.

when i exporting i have wind influence but only on brunch and twigs. the leaves just moving with them.

someone know hot to get wind influence also on the meshes leaves?

wind leaves like this:

https://youtu.be/gdpJ-akDGdw?t=14
https://youtu.be/s3xUoSuJqDM?t=67

many thanks