forage for food
This command allows you to forage for food, more successfully in some areas than others. It helps reduce the amount of food you need to carry, trips to civilization for meals, or eating clerical food. Do remember that the food might be poisoned.

forage for herbs
This command allows you to forage for herbs which can be used for brewing.

forage for wood
This command allows you to find blocks of wood used in crafting.

Success rate, time required, and how edible it will be are improved by higher levels in the survival skill, but are also affected by the terrain.