Making a doctor in Little Alchemy 2 is quite easy. First, combine Life and Time to create a Human. Then, combine Human and Knowledge to create a Doctor. Alternatively, you can make a Doctor by combining Science and Life.
In order to make a Doctor more interesting and unique, you can also try combining different elements with the Human element such as Medicine, Nature, or Technology. Combining Human with Medicine will create a Nurse, Human with Nature will create a Shaman, and Human with Technology will create a Robotics Engineer. Experimenting with different combinations will keep the game interesting and will allow you to create more unique doctors.
