Haza studied in the Conservatoire of Santo Domingo and debuted on 13 March 1958 as a singer, in a chamber concert celebrated in the presence of the dictator Rafael Trujillo. In 1961 she studied in the Conservatoire of Music Santa Cecilia in Rome with Elena D'Ambrossio, Inés Alfani-Tellini and Roberto Caggiano. Haza’s repertoire covers all the genres of vocalic music, from operetta and opera to requiems and symphonic poems as well as songs and hymns. With the National Symphonic Orchestra of the Dominican Republic she presented under the direction of the Dominican Teachers Manuel Simó, Carlos Piantini, Rafael Villanueva, Julio de Windt, Manuel Marino Miniño, and José Antonio Molina and guest directors of orchestra like Roberto Caggiano, Carlos Chávez, Enrique García Asencio, Paul Engel and Robert Carter Austin. Some of her more important musical colleagues are Olga Chance, Arístides Incháustegui, Luís Rivera, Roberto Caggiano, Lilliam Column, Jacinto Gimbernard, Luis Cold Sandoval, Rafael Félix Gimbernard, Rafael Sánchez Cestero, Rafael Félix, Manuel Simó, Dagmar White, Creole Hidalgo, Fausto Cepeda, Luis Cold, Rafael Gil Castro, Vito Castorina, and Enriquillo Cerón. Haza sang works by Maurice Ravel, Heitor Villa-Wolves, Lukas Foss, José of Jesús Ravelo, Leo Brouwer and Enrique of Marchena. She played some of the leading roles in operas like Cavalleria rusticana, The Clowns, The Zarzuelas, Luisa Fernanda, The legend of the kiss, and The cafetal. Outside of the Dominican Republic, she has performed in the United States, Puerto Rico, Mexico, and Cuba. She participated with pianist Manuel Rueda in the Latin Festival-American of the Arts. In 1988, she participated in the Festival Cervantino in Mexico and the Dominican Republic with the pianist María of Fátima Geraldes. That same year she recorded the CD's Delivery, Jewels of Navidad and Dreams. Additionally, Haza taught during many years in the National Conservatoire of Music, was artistic director of the National Theatre for five years, and directed the Lyric Singers of Fine Arts. She has been honored by the Order of the Dominicos of Duarte of Sánchez and Mella of Dominican Republic and the Order of the Merit of Italy.
