* Currently configuration supports:
* 1. query-time boosting, user could set how to boost each field.
* 2. boolean model chosing, user could choose which boolean model to use for each field.
* 3. token expandation, user could set token expand to True to improve Recall. Default is False.
* Currently configuration supports:
* 1. query-time boosting, user could set how to boost each field.
* 2. boolean model chosing, user could choose which boolean model to use for each field.
* 3. token expandation, user could set token expand to True to improve Recall. Default is False.