Resolves: #460613
    Summary: Approximate Search '~=' Returns unexpected result
    Change description: increasing the maximum length of "phonetic" string from 4
    to 6.  The length 4 is sometimes too short to distinguish long words.  For
    instance, the sample string Queensland is converted to KNSLNT if there is no
    limitation; Consulting is to KNSLTNK.  By cutting them at the 5th character,
    the 2 strings are considered to sound like each other.