bulk up (someone's) resume

Translations
улучшить (чей-то) резюме
He took extra courses to bulk up his resume.
Он прошёл дополнительные курсы, чтобы улучшить своё резюме.
Definitions
To add experiences, skills, or qualifications to someone's resume in order to make it appear more impressive or substantial, often to improve their chances of getting a job.