Perhaps you should try some spelling variations:
petr » peter (Expand Search), petri (Expand Search), petru (Expand Search)
petroi » peteroi (Expand Search), petrioi (Expand Search), petruoi (Expand Search), petri (Expand Search), petro (Expand Search), petrov (Expand Search)
petrowv » peterowv (Expand Search), petriowv (Expand Search), petruowv (Expand Search), petrov (Expand Search), petrow (Expand Search), petrowna (Expand Search)
petrois » peterois (Expand Search), petriois (Expand Search), petruois (Expand Search), petris (Expand Search), petros (Expand Search), petrovs (Expand Search)
peteri » peterdi (Expand Search), peter (Expand Search), petri (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 (petr OR ((petroi OR peteri) OR ((petrowv OR petrowv) OR (petrois OR petrois)))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop (petr OR ((petroi OR peteri) OR ((petrowv OR petrowv) OR (petrois OR petrois)))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop (petr OR ((petroi OR peteri) OR ((petrowv OR petrowv) OR (petrois OR petrois)))) o.s.*.