Therain or Therein: How To spell?

The word Therain is misspelled against Therein, an adverb meaning "In that or this place, time, or thing; in that particular or respect."

Word contains consecutive vowels 'EI' in between alphabets ther & n is misspelled as 'AI'
Wrong Spelling:  ther-ai-n 
Correct Spelling:  ther-ei-n 
Find more wrongly spelled words of Therein to spell it well.