Your dog has a yeast infection caused by Malssezia. She probably has ear infections caused by the same fungus. The tar shampoo will help but she probably needs to be on an oral antifungal medication and topical medication and cleaner for her ears. Your veterinarian may have an antifungal shampoo that would be more effective than the tar shampoo. Which every you use, leave it on for several minutes contact time and bathing in cool water will also help relieve itching. Oral antifungal medication will likely be needed for weeks or even months. Antibiotics may be necessary for secondary bacterial infections.