The 20-year-old was spotted carrying a copy of 'The 5 Languages of Love: The Secret to Love That Lasts' as she left a salon in West Hollywood, reported Daily Mail.
Written by relationship counselor and New York Times bestselling author Gary Chapman, it gives advice on words of affirmation, quality time, receiving gifts, acts of service and physical touch.
Gomez, who has been busy promoting her upcoming film "Spring Breakers" in recent months, has been dating Bieber, 18, for two years.
