*- filter the term "quot" from queries*
quot or " ?
*- filter 14###########: from the front of queries*
UNIX time? 1437794758
*- replace _ with space in queries*
Do you have actual URL of the search? [[Special:Search/this_format]] is supposed to ignore underscores already
Also, a full text search URL containing "search=" but not "fulltext=" is first of all a title search (the aim is to be redirected to the title if it exists).
For the incremental searches, do we know if all browsers which integrate a Wikipedia search bar use the correct API for suggestions?