While it is possible to vacuum little rocks, the process is usually not recommended. Vacuuming small stones can cause damage to your vacuum cleaner and may even jam it (if you are not properly cautious). Additionally, vacuuming little rocks can create a dust cloud that could trigger asthma or other respiratory problems in people sensitive to particles. If you must remove little rocks from your carpets, then a sweeper or broom should be sufficient. You can use a HEPA shop vac as a safer option.