Perhaps you should try some spelling variations:
petr » petru (Expand Search), petro (Expand Search)
petrou » petruou (Expand Search), petroou (Expand Search), petru (Expand Search), petro (Expand Search), petrov (Expand Search)
petroou » petruoou (Expand Search), petrooou (Expand Search)
petri » petrui (Expand Search), petroi (Expand Search)
petroi » petruoi (Expand Search), petrooi (Expand Search), petro (Expand Search), petrov (Expand Search), petrow (Expand Search)
petroov » petruoov (Expand Search), petrooov (Expand Search), petrov (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 (((peter OR (per OR petr)) OR (petrou OR petroou)) OR (petri OR (petroi OR petroov))) _. s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (((peter OR (per OR petr)) OR (petrou OR petroou)) OR (petri OR (petroi OR petroov))) _. s.".
• Adding a wildcard symbol may retrieve word variants: fop (((peter OR (per OR petr)) OR (petrou OR petroou)) OR (petri OR (petroi OR petroov))) _. s.*.