Perhaps you should try some spelling variations:
peterov » petrov (Expand Search)
petriov » petrov (Expand Search), petriiov (Expand Search), petruiov (Expand Search), petroiov (Expand Search)
petroi » petri (Expand Search), petro (Expand Search), petrov (Expand Search), petrioi (Expand Search), petruoi (Expand Search), petrooi (Expand Search)
petroiuo » petriuo (Expand Search), petrouo (Expand Search), petrovuo (Expand Search), petrioiuo (Expand Search), petruoiuo (Expand Search), petrooiuo (Expand Search)
petriuoov » petriiuoov (Expand Search), petruiuoov (Expand Search), petroiuoov (Expand Search)
petr » petri (Expand Search), petru (Expand Search), petro (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 ((peterov OR (petriuoov OR petriov)) OR ((petroi OR petroiuo) OR (petr OR peter))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((peterov OR (petriuoov OR petriov)) OR ((petroi OR petroiuo) OR (petr OR peter))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((peterov OR (petriuoov OR petriov)) OR ((petroi OR petroiuo) OR (petr OR peter))) o.s.*.