Caraway seeds are a flavorful spice used in many dishes, but sometimes you may not have them on hand. If that happens, you can try substituting them with fennel seeds, cumin seeds, or anise seeds. However, be aware that each of these spices has a distinct taste, and your dish may turn out slightly different than expected. Another option is to use ground caraway seeds, which will still give your dish the signature flavor but will be less distinct. Other similar spices that you could try include coriander seeds, mustard seeds, and nigella seeds. Experimenting with different spices can lead to unexpected and delicious flavor combinations!