Perhaps you should try some spelling variations:
change dealing » change leading, change modelling, change learning
gender change » gender age
yang guang » yang yang, yan guan, yang liang
wang yang » wang yan, wang liang, wang yanling
date sub » data sub, note sub
case sub » case sums, case s0
die spur » der spur
guang 2 » guang eu, zugang 2

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: wang yang guang 2 gender change dealing ((((date sub) OR (case sub))) OR (die spur)) ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang yang guang 2 gender change dealing ((((date sub) OR (case sub))) or (die spur)) ;~".
• Adding a wildcard symbol may retrieve word variants: wang yang guang 2 gender change dealing ((((date sub) OR (case sub))) or (die spur)) ;*.