Perhaps you should try some spelling variations:
ruhr » ruhe (Expand Search), nuhr (Expand Search)
rohr » mohr (Expand Search)
lohr » lehr (Expand Search), lahr (Expand Search), mohr (Expand Search)
mohn » john (Expand Search), mahn (Expand Search), mohr (Expand Search), mohne (Expand Search), mjohn (Expand Search)
ohn » ohne (Expand Search), john (Expand Search)
bohn » bohne (Expand Search), bjohn (Expand Search)
hohn » hohne (Expand Search), hjohn (Expand Search), hahn (Expand Search), huhn (Expand Search)
sohn » sohne (Expand Search), sjohn (Expand Search)
university » universitat (Expand Search)

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((ruhr OR rohr) OR ((lohr OR ((mohn OR ohn) OR bohn)) OR (hohn OR sohn))) university bochum~".
• Adding a wildcard symbol may retrieve word variants: ((ruhr OR rohr) OR ((lohr OR ((mohn OR ohn) OR bohn)) OR (hohn OR sohn))) university bochum*.