When confronted with a difficult or impossible problem, dogs tend to look back at humans and try to catch their attention, instead of trying to solve it themselves. This behavior has been interpreted as a help request, but it is debated whether dogs take into account prior experiences with people when selecting whom to turn to. In the present study, dogs were trained to discriminate between a generous experimenter who gave them food and a selfish one that took it away. After assessing that they had established a preference for the generous one, we exposed them to an unsolvable task in which food was locked inside a container, while the experimenters stood on each side of the apparatus. During this task, we measured their behaviors towards each experimenter. Results showed that dogs did not first turn to the generous experimenter. However, they gazed more at the generous experimenter during the task, which implies that they did, to some degree, selectively ask for help based on previous interactions. Moreover, they gazed more and spent significantly more time in contact with the female experimenter when she was generous, suggesting a possible synergic effect of the experimenters’ ID (male/female) and their attitude (generous/selfish). All in all, these results suggest that, to some extent, dogs are able to use the information from previous interactions with unknown humans to selectively ask for help.