Well, the quick answer is "use a straight; it will help". The serious answer is yes, with a properly sharp razor & good technique, you should be able to vastly reduce, if not eliminate them.

They're caused by beard hairs growing back into the skin, a common symptom of shaving too close in susceptible areas. The nice thing about a single blade is , with experience, you can shave basically right up to the limit (for you; everyone is different), & not exceed it.