Require diacriticals to match when searching for words in an accent-optional index.

If an index was created with the dtsIndexCreateOptionalAccentSensitive, then at search time accents in search requests can be either required for a match or ignored. Set dtsSearchRequireAccents to make accents required. 

In an accents-optional index, accented letters can be made significant for matching purposes, but unaccented letters will still always match both accented and unaccented forms. 

For example, a search for "abc" will find both "abc" and "äbc". A search for "äbc" will find "äbc" and will find "abc" as well if dtsSearchRequireAccents is not set.