Perhaps you should try some spelling variations:
gender class » gender biases, gender bias
class call » class case
wang yang » wang yan, wang yanling
4 gender » 2 gender, 3 gender, 1 gender
call die » cavell die, call date, call me
die spur » der spur
yan 4 » yang 4, yan _, ban 4

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((wang liang) or (wang yang)) yan 4 gender class call die spur ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((wang liang) OR (wang yang)) yan 4 gender class call die spur ;*.