Perhaps you should try some spelling variations:
peri » petri (Expand Search), per (Expand Search)
petroov » peteroov (Expand Search), petrioov (Expand Search), petrooov (Expand Search)
petriov » peteriov (Expand Search), petriiov (Expand Search), petroiov (Expand Search)
petruuiov » peteruuiov (Expand Search), petriuuiov (Expand Search), petrouuiov (Expand Search)
petruiv » peteruiv (Expand Search), petriuiv (Expand Search), petrouiv (Expand Search)
petru » peteru (Expand Search), petriu (Expand Search), petrou (Expand Search)
petr » peter (Expand Search), petri (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 ((((petroov OR petriov) OR petruuiov) OR petruiv) OR (((pero OR petru) OR peri) OR petr)) o.s.~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "fop ((((petroov OR petriov) OR petruuiov) OR petruiv) OR (((pero OR petru) OR peri) OR petr)) o.s.".
• Adding a wildcard symbol may retrieve word variants: fop ((((petroov OR petriov) OR petruuiov) OR petruiv) OR (((pero OR petru) OR peri) OR petr)) o.s.*.