2018–2020: Early career and Star Hunt Academy audition Prior to joining Bini, Jhoanna had
bit roles in the
soap opera Kadenang Ginto (), where she portrayed the schoolmate of
Andrea Brillantes and
Francine Diaz' characters Marga and Cassy, as well as the drama anthology series
Maalaala Mo Kaya (). On October 10, 2020, Jhoanna was one of the last eight members of the SHA Girl Trainees to graduate and was officially announced as a member of an idol group. In November 2020, Jhoanna officially became a member of the Filipino girl group
Bini.
2021–present: Debut with Bini, acting ventures, and expanding music career Jhoanna officially debuted as a member of Bini on June 11, 2021. She is officially the group's leader, in addition to being one of its lead vocalists and rappers. In June 2022, Jhoanna's vocal abilities earned praise from
Parcinq's Hans Ethan Carbonilla, who wrote that she had "one of the best voices in P-pop". In 2023, she starred in the music video for "
Maharani" () by the
Pinoy pop boy band
Alamat. In the video, she and the members of Alamat portray classmates who are rehearsing for a school performance of the
singkil traditional dance. As they practice, a spark grows between Jhoanna and the Alamat member
Taneo Sebastian. Rafael Bautista of
Nylon Manila remarked that "it felt correct" for Jhoanna and Taneo to portray the lead couple, as they are both the official leaders of their respective groups. She learned how to dance
singkil for the video. Later that year, she was cast as Epifania "Eds/Panyang" delos Santos, the female lead of
Tabing Ilog the Musical, a role she alternated with
Vivoree Esclito and
Sheena Belarmino. It is a
musical theater adaptation of
Tabing Ilog (), a teen drama series that originally aired from 1999 to 2003. The musical updates the show's story and setting to suit its
Gen Z cast and characters. In 2024, she reprised the role, along with Esclito and Belarmino. The rerun lasted from November 8 to December 1. Jia Pizarro Bote of
When in Manila lauded Jhoanna's stage performance, writing that she proved her versatility as Eds. The musical is a joint production between the
Philippine Educational Theater Association (PETA) and
ABS-CBN. She was also a featured vocalist on "Kalma Kahit Magulo" (), a song from the original soundtrack of the 2024
ABS-CBN drama series
High Street, along with fellow Bini member
Colet and
Juan Karlos Labajo. In 2025, Jhoanna drew controversy when a video circulated, appearing to show her with two male companions, Ethan David of
GAT and dancer Shawn Castro. The clip also featured what fans believed to be the voices of two other Bini members. The two men acted out a sexually suggestive scene. Amid concerns that the men's simulated act involved an underage girl, Castro clarified in his apology that "no minor, or anyone, was hurt physically, mentally, sexually, or in any manner". David and Bini also issued public apologies. On July 31, Jhoanna attended a special screening of
Sunshine, a film led by
Maris Racal that discusses themes including
abortion,
reproductive health, and
safe sex in the Philippines. After the screening, Robles shared her thoughts, commending the film's focus on
mental health and expressing that individuals facing mental challenges may sometimes make decisions based on short-term relief. Her remarks drew mixed reactions online, with some
netizens that her comments appeared an overshadow the film's central message and reflected a perceived "pro-life" bias. Robles later issued a public apology via Instagram, acknowledging the concerns. The film director,
Antoinette Jadaone, defended Robles, noting that public figures may face limitations when addressing sensitive subjects like abortion. In January 2026, Jhoanna appeared in the short film
The Witness. == Other ventures==