Perhaps you should try some spelling variations:
petruov » petrov (Expand Search), petriuov (Expand Search), petruuov (Expand Search), petrouov (Expand Search)
petris » petri (Expand Search), petriis (Expand Search), petruis (Expand Search), petrois (Expand Search)
peris » paris (Expand Search)
petr » petri (Expand Search), petru (Expand Search), petro (Expand Search)
petroi » petrioi (Expand Search), petruoi (Expand Search), petrooi (Expand Search), petri (Expand Search), petro (Expand Search), petrov (Expand Search)
petroooi » petrioooi (Expand Search), petruoooi (Expand Search), petrooooi (Expand Search)

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: fop (petruov OR ((petris OR peris) OR (((petr OR petroi) OR petroooi) OR peter))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (petruov OR ((petris OR peris) OR (((petr OR petroi) OR petroooi) OR peter))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (petruov OR ((petris OR peris) OR (((petr OR petroi) OR petroooi) OR peter))) o.s.*.