Combine all-purpose flour, whole wheat flour, salt, baking powder, rosemary, sesame seeds, flax seeds, and poppy seeds in a large mixing bowl.

Add olive oil and water to the dry ingredients, then mix until a shaggy dough forms.

Transfer the dough to a lightly floured surface and knead briefly until it becomes smooth and cohesive.

Divide the dough in half and roll each portion very thinly between two sheets of parchment paper using a rolling pin.

Place the rolled dough on parchment paper onto baking sheets and score it into desired cracker shapes with a sharp knife or pizza cutter.

Bake the crackers at 350°F (175°C) for 20-25 minutes, or until they are golden brown and crispy.

Allow the crackers to cool completely on a wire rack before breaking them apart and serving.