The reason why milk cannot be sucked out is considered to be incorrect operation method on the one hand and possible blockage of breast ducts on the other hand. In this case: 1. If you are not able to suck out the milk with a breast pump, you can go to the gynecology or obstetrics department of a regular public hospital and ask professional medical staff to help suck out the milk. 2. If you are still unable to suck out the milk with a breast pump, you can use local massage and warm towels to promote the discharge of milk. 3. There is also a special way to unblock the milk ducts, which is to let your husband suck on the nipple.