Regression:Special characters are ignored in search & documents with special characters are not shown in search result

Steps to reproduce:-->
1.open cms https://cms.demo.test.onehippo.com/?0
2.create a document "doc1" with text "aeiouy"
3.create another document "doc2" with text áèïõūÿ
4.Save the documents.
5.Go to search box in navigation panel.
6.type "áèïõūÿ" in the searchbox & click search button.
7.Notice only "doc1" is visible in search result.

Expected:--Both the documents "doc1","doc2" should be shown in search results.

Note:-->search is working fine when checked in latest release at https://cms.demo.onehippo.com/?0