This trial is testing lenvatinib and pembrolizumab in patients with advanced Adenoid Cystic Carcinoma or other salivary gland cancers that have come back or spread. Lenvatinib stops cancer cells from growing, while pembrolizumab helps the immune system attack the cancer. Researchers aim to see if these drugs are effective and safe for these patients. Lenvatinib and pembrolizumab have shown promising results in treating various advanced cancers, including thyroid, liver, endometrial, and gastric cancers.