Perhaps you should try some spelling variations:
2.1 early » 1.1 early, 11 early
2f early » 21 early, ef early, 2.3 early
sf early » ef early, self early, imf early
23 early » 2.3 early, 3 early, 13 early
20 early » 10 early, 1820 early, 1720 early
f early » ef early, 5 early, 8 early

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: %natural theology %((((((((((2f early) OR (2.1 early))) OR (sf early))) OR (f early))) OR (23 early))) OR (20 early)) works to 1800%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%natural theology %((((((((((2f early) OR (2.1 early))) or (sf early))) or (f early))) or (23 early))) or (20 early)) works to 1800%22".
• Adding a wildcard symbol may retrieve word variants: %natural theology %((((((((((2f early) OR (2.1 early))) or (sf early))) or (f early))) or (23 early))) or (20 early)) works to 1800%22*.