Perhaps you should try some spelling variations:
natural topology » natural theology, neural topology, natural phonology
1720 early » 1727 early, 1820 early, 1770 early
22 early » 12 early, 1722 early, 1.2 early
20 early » 10 early, 1820 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 topology %((((22 early) OR (2 early))) OR (((((20 early) OR (1720 early))) OR (18((20 early) OR (1720 early)))))) works to 1800%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%natural topology %((((22 early) or (2 early))) or (((((20 early) OR (1720 early))) or (18((20 early) OR (1720 early)))))) works to 1800%22".
• Adding a wildcard symbol may retrieve word variants: %natural topology %((((22 early) or (2 early))) or (((((20 early) OR (1720 early))) or (18((20 early) OR (1720 early)))))) works to 1800%22*.