Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Indonesia to Yemen as you normally would.
This is defined as Denpasar Bali Ngurah Rai Airport (DPS) and Aden Airport (ADE). Codes like Aden Airport are often used to just call airports uniquely. Sanaa Sana'a Intl Airport (SAH), Al Mukalla Riyan Mukalla Airport (RIY) are other airports near this flight route and their unique identifiers/IATA codes.