Perhaps you should try some spelling variations:
petroiov » petrov (Expand Search), peteroiov (Expand Search), petrioiov (Expand Search), petruoiov (Expand Search)
petriiov » petrov (Expand Search), peteriiov (Expand Search), petriiiov (Expand Search), petruiiov (Expand Search)
petruv » peteruv (Expand Search), petriuv (Expand Search), petruuv (Expand Search)
petroi » peteroi (Expand Search), petrioi (Expand Search), petruoi (Expand Search)
petrui » peterui (Expand Search), petriui (Expand Search), petruui (Expand Search)
petruooui » peteruooui (Expand Search), petriuooui (Expand Search), petruuooui (Expand Search)
petr » peter (Expand Search), petri (Expand Search), petru (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 ((petruv OR (petroiov OR petriiov)) OR (((petroi OR petrui) OR petruooui) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((petruv OR (petroiov OR petriiov)) OR (((petroi OR petrui) OR petruooui) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((petruv OR (petroiov OR petriiov)) OR (((petroi OR petrui) OR petruooui) OR petr)) o.s.*.