Complex sentence: A jewellery store (American English: jewelry store) is a retail business establishment, that specializes in selling (and also buying) jewellery and watches, also provide many services such as repairs, remodeling, restoring, designing and manufacturing pieces.
Split into simpler sentences: A jewellery store (American English: jewelry store) is a retail business establishment, that specializes in selling (and also buying) jewellery and watches. Jewellery stores provide many services such as repairs, remodeling, restoring, designing and manufacturing pieces.