Advertisements exaggerate, so they can't be fully trusted.
Tips
mistakes
夸大其辞 and 夸大其词 are both attested and pronounced identically (kuādàqící). 词 ('word') is the more common modern form, while 辞 ('speech, statement') is the older variant. Both are correct.
history
Traceable to Song-dynasty scholar 楼钥's 《攻媿集·论灾异》: 祥瑞之出，则润色而张大其词 ('When auspicious omens appear, people embellish and exaggerate them').
