Jin Ben Qiang Fa - Basic Spear Techniques - Técnicas Base de Lança 

If you mean the spear head, yes it can't, because the spear head used in video is just for beginner and demonstration purpose. The real spear head applied in battlefield of ancient China is lethal. But if you mean the spear punch technique cannot pierce through heavy armor, no it can, not only can, it is the most powerful spear thrust with longest reach. Stay close with the moment when spear is being punched out to make a thrust, hand at the back is being rotated while moving forward to reach the static hand at front through a distance. With this distance and rotation, huge thrusting momentum is generated. Just like a rotated straight punch of Karate/Taekwando or any other renowned martial art's punching technique, enough to pierce through any armour once such technique is combined with real razor sharp spear head. Try learning Kung Fu Martial Art, you will learn to use different weapons in different chapters. Spear is one of them, it is one of the most indispensable essence to master and understand how force should be properly applied in combat. You can feel the fierce power of a spear being punched out to make a thrust if your technique is properly guided and applied. You just don't feel this kind of power in other spear techniques other than Chinese spear technique. Chinese had unified and standardized the size and design of each spear, only to be distributed to every soldier in an army INCLUDING PEASANTS. Which is unlike Europeans ancient warfare where peasants just bring their axes and sticks to battlefield while strong spear was only for knights and soldiers. In terms of spear warfare, spear technique and spear formation research, Chinese are specialist till today. Modern HEMA originated in western world includes a huge variety of ancient weapons for sparring, but modern China have so many ancient weapon sparring organization which ONLY teach and practice spear sparring. Imagine how specialized it is. Below video for reference: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-AVvGMHS5HYU.html