Fix #1914910 [Annotations Browser: Error when searching for punctuation](https://bugs.launchpad.net/calibre/+bug/1914910)

src/calibre/gui2/library/annotations.py

@@ -17,6 +17,7 @@ from urllib.parse import quote
 
 from calibre import prepare_string_for_xml
 from calibre.ebooks.metadata import authors_to_string, fmt_sidx
+from calibre.db.backend import FTSQueryError
 from calibre.gui2 import Application, choose_save_file, config, error_dialog, gprefs
 from calibre.gui2.dialogs.confirm_delete import confirm
 from calibre.gui2.viewer.widgets import ResultsDelegate, SearchBox
@@ -543,6 +544,7 @@ class BrowsePanel(QWidget):
         if q == self.current_query:
             self.results_list.show_next(backwards)
             return
+        try:
             with BusyCursor():
                 db = current_db()
                 if not q['fts_engine_query']:
@@ -559,6 +561,12 @@ class BrowsePanel(QWidget):
                     )
                 self.results_list.set_results(results, bool(q['fts_engine_query']))
                 self.current_query = q
+        except FTSQueryError as err:
+            return error_dialog(self, _('Invalid search expression'), '<p>' + _(
+                'The search expression: {0} is invalid. The search syntax used is the'
+                'SQLite Full text Search Query syntax, <a href="{1}">described here</a>.').format(
+                    err.query, 'https://www.sqlite.org/fts5.html#full_text_query_syntax'),
+                det_msg=str(err), show=True)
 
     def effective_query_changed(self):
         self.do_find()