Perhaps you should try some spelling variations:
petriv » petrov (Expand Search), peteriv (Expand Search), petruiv (Expand Search), petroiv (Expand Search)
petroiv » petrov (Expand Search), peteroiv (Expand Search), petruoiv (Expand Search), petrooiv (Expand Search)
petriu » petru (Expand Search), peteriu (Expand Search), petruiu (Expand Search), petroiu (Expand Search)
petris » peteris (Expand Search), petruis (Expand Search), petrois (Expand Search)
petruis » peteruis (Expand Search), petruuis (Expand Search), petrouis (Expand Search)
petr » peter (Expand Search), petru (Expand Search), petro (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (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 ((petriv OR petroiv) OR ((petriu OR ((petris OR petruis) OR petruis)) OR (petr OR petri))) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petriv OR petroiv) OR ((petriu OR ((petris OR petruis) OR petruis)) OR (petr OR petri))) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petriv OR petroiv) OR ((petriu OR ((petris OR petruis) OR petruis)) OR (petr OR petri))) o.s.*.