Subject headings, and names used as headings, are always spelled the same way, but names may spelled differently in book and article titles
TIPS:
1) Always use truncation
Just enter the last name, then add the ? after it to search for any possible endings
(i.e.: Beethoven?)
will yield results with possessives, such as
Beethoven's Life
2) Try alternate spellings of composer names
(i.e.: Tchaikovsky OR Tchaikowsky OR Chaikovsky etc.)
3) Remember: using a name as a subject will bring up works about someone; using a name as an author will bring up work only by them