Hello, @Admin,
The product images/thumbnails are handled by WooCommerce, and the product images/thumbnails are blurry could be because of the Incorrect image resizing.
Please read and follow the instructions written in the official documentation of the WooCommerce for fixing blurry product images here: https://woocommerce.com/document/fixing-blurry-product-images/
I hope this will solve your issue.
Best Regards,
PThemes Team.