Perhaps you should try some spelling variations:
petruov » peteruov (Expand Search), petruuov (Expand Search), petrouov (Expand Search)
petrooiov » peterooiov (Expand Search), petruooiov (Expand Search), petroooiov (Expand Search)
petruuiov » peteruuiov (Expand Search), petruuuiov (Expand Search), petrouuiov (Expand Search)
petri » peteri (Expand Search), petrui (Expand Search), petroi (Expand Search)
petrooi » peterooi (Expand Search), petruooi (Expand Search), petroooi (Expand Search)
petr » peter (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 ((petruov OR (petrooiov OR petruuiov)) OR ((per OR (petri OR petrooi)) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petruov OR (petrooiov OR petruuiov)) OR ((per OR (petri OR petrooi)) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petruov OR (petrooiov OR petruuiov)) OR ((per OR (petri OR petrooi)) OR petr)) o.s.*.