Perhaps you should try some spelling variations:
relational language » rational languages, national language, regional language
plain language » latin language
2f grammar » 2 grammar, 22 grammar, 26 grammar
2 grammars » _ grammars, 1 grammars, 2 grammar
2f early » 21 early, ef early, f early
20 early » 10 early, 1820 early, 1720 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: %((plain language) OR (relational language)) %((2f grammar) OR (2 grammars)) %((2f early) OR (20 early)) works to 1800%22.
• Adding a wildcard symbol may retrieve word variants: %((plain language) or (relational language)) %((2f grammar) or (2 grammars)) %((2f early) or (20 early)) works to 1800%22*.