Perhaps you should try some spelling variations:
petriov » petrov (Expand Search), petriiov (Expand Search), petruiov (Expand Search), petroiov (Expand Search)
petruv » petru (Expand Search), petrov (Expand Search), petriuv (Expand Search), petruuv (Expand Search), petrouv (Expand Search)
peteru » petru (Expand Search), peters (Expand Search)
petruiiuv » petriuiiuv (Expand Search), petruuiiuv (Expand Search), petrouiiuv (Expand Search)
petruiiiuv » petriuiiiuv (Expand Search), petruuiiiuv (Expand Search), petrouiiiuv (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 ((petriov OR (petruv OR (petruiiuv OR petruiiiuv))) OR (peteru OR (petr OR peter))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriov OR (petruv OR (petruiiuv OR petruiiiuv))) OR (peteru OR (petr OR peter))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petriov OR (petruv OR (petruiiuv OR petruiiiuv))) OR (peteru OR (petr OR peter))) o.s.*.