Perhaps you should try some spelling variations:
20 formulae » 10 formulae, 2 formulae, 20 formula
2 formulas » _ formulas, 3 formulas, cnf formulas
c receipts » _ receipts, new receipts, all receipts
2.1 early » 1.1 early, 11 early
21 early » 11 early, 1.1 early

Try widening your search to All Fields.

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: %22medicine %((2 formulas) OR (20 formulae))%c receipts%_ prescriptions %((21 early) OR (2.1 early)) works to 1800%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22medicine %((2 formulas) or (20 formulae))%c receipts%_ prescriptions %((21 early) OR (2.1 early)) works to 1800%22".
• Adding a wildcard symbol may retrieve word variants: %22medicine %((2 formulas) or (20 formulae))%c receipts%_ prescriptions %((21 early) OR (2.1 early)) works to 1800%22*.