I think they're saying tho that in one case "bread" means a kind of food, and in the other, it means money. If the different uses were more directly connected to particular words that could disambiguate, it wouldn't be too hard -- head features typically can do this -- but the disambiguation here is far more conceptual in original. You know that you need money to buy things, and so you know that not having money is a good reason for not being able to buy things. But bread-the-food is not needed to buy things, so not having it isn't a good reason for not being able to buy things. So probably the second "bread" is the bread-money version. This kind of disambiguation is super tricky without broader world knowledge.