If they’d written “12 Super-Easy Hair Looks Every Woman Can Do in 5 Minutes”, then the “5 minutes” would have counted as a power phrase, too!
“Kate Middleton” is a power word, too – I bet the audience of that post all want to look like her 🙂
It’s quite normal to feel clueless at first. You’re doing well. It takes time to get a feel for patterns and to notice what works and what doesn’t (and that can vary for different audiences, too).
Enchant readers. Woo customers. Win business.