Make some changes on filters

Change the StringSearchOption from Contains Exactly to Identical To
Reset the filter if the user tries to use only blank spaces
Create a new StringSearchOption (Contains Exactly) wich will search for that
string, exactly how it is. eg: searching for  'maria', results can be
'ana maria', 'mariangela', but if you search for 'maria ' (with a blank
space at end of the string), the results wont have 'mariangela'

Change-Id: Ibc2caf6d8c4cb631a2383f69bc5a0ea5b23d3ccd