.

if you don't want to use leitmotif you could say

continues to be a recurring theme

http://www.dresslab.com/notes/flowers-from-the-past/
Where did the seed of this trend lie? Is it a one-off event or are flowers a recurring theme? Are trends cyclical, less persistent than we thought?

The Canadian designer Erdem Moralioglu has picked them as a recurring theme in six of his last collections, and though it might seem impossible, has not bored us yet.

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Note added at 30 mins (2017-05-18 16:55:38 GMT)
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continueS if the subject is singular ie: embroidery!

It would help if you gave more context. I am guessing that the fabric is floral and the embroidery is too; I would avoid an overly-literal translation of "confirm", I think it's a bit clunky.

Alternatively "The floral theme is picked up in the embroidery".

My take, anyway. Buon lavoro a tutti!