How to transfer purchased theme for another project?


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Hi there,
Im newbie to Webflow community, I would like to ask, how can I transfer my purchased theme(left project) into the current project(right project) I have been working on, the current project has site plan which includes cms too. when I was purchasing the themes it created a new project, but I don’t know how to add the theme into the current project I have been working on, looking forward to any advice, Thank you.