putting exact matches first in elasticsearch multimatch query - lucene

Question

it sure seems that there's no easy way to do this ... how can i ensure that certain fields in my multi match query going to actually be boosted correctly so that exact matches show up at the top?
i honestly seem to have tried this a multitude of ways, but maybe someone knows the answer ...
in my movie and music database, i'm trying to search multiple fields at once, but ensure that exact matches make it to the top and that certain fields such as title and artist name have more boost.
here's the main portion of my query...
"query": {
"bool": {
"should": [
{
"multi_match": {
"type": "phrase_prefix",
"query": "brave",
"max_expansions": 10,
"fields": [
"title^3",
"artists.name^2",
"starring.name^2",
"credits.name",
"tracks^0.1"
]
}
}
],
"minimum_number_should_match": 1
}
}
as you see, the query is 'brave'. it just so happens there's a movie called brave. perfect, i want it at the top - since not only is it an exact match, but the match is in the title. however, there's a popular song called 'brave' from sara bareilles which ends up on top. why?
i've tried every analyzer known to man, custom and otherwise, and i've tried changing the 'type' parameter to every other permutation (phrase, best_fields, cross_fields, most_fields), and it just doesn't seem to honor the fact that i'm effectively trying to either promote 'title' and 'artists.name' and 'starring.name' and DEMOTE 'tracks'.
is there any way i can ensure all exact matches show up at the top (especially in title, etc) followed by expansions, etc?
any suggestions would be helpful.
EDIT
the analyzer i'm currently using which seems to work better than others is a custom one i call 'nameAnalyzer' which is made up of a 'lowercase' filter and 'keyword' tokenizer only.
here's some example documents in the order in which they're appearing in the results:
fields": {
"title": [
"Brave"
],
"credits.name": [
"Kelly MacDonald",
"Emma Thompson",
"Billy Connolly",
"Julie Walters",
"Kevin McKidd",
"Craig Ferguson",
"Robbie Coltrane"
],
"starring.name": [
"Emma Thompson",
"Julie Walters",
"Billy Connolly",
"Kevin Mckidd",
"Kelly Macdonald"
]
,
fields": {
"credits.name": [
"Hilary Weeks",
"Scott Wiley",
"Sarah Sample",
"Debra Fotheringham",
"Dustin Christensen",
"Russ Dixon"
],
"title": [
"Say Love"
],
"artists.name": [
"Hilary Weeks"
],
"tracks": [
"Say Love",
"Another Second Chance",
"It's A Good Day",
"Brave",
"I Found Me",
"Hero",
"Tell Me",
"Where I Am",
"Better Promises",
"Even When"
]
,
fields": {
"title": [
"Brave Little Toaster"
],
"credits.name": [
"Randy Bennett",
"Jim Jackman",
"Randy Cook",
"Judy Toll",
"Jon Lovitz",
"Tim Stack",
"Timothy E. Day",
"Thurl Ravenscroft",
"Deanna Oliver",
"Phil Hartman",
"Jonathon Benair",
"Joe Ranft"
],
"starring.name": [
"Jon Lovitz",
"Thurl Ravenscroft",
"Tim Stack",
"Timothy E. Day",
"Deanna Oliver"
]
},
"fields": {
"title": [
"Braveheart"
],
"credits.name": [
"Bernard Horsfall",
"Martin Dempsey",
"James Robinson",
"Robert Paterson",
"Alan Tall",
"Rupert Vansittart",
"Donal Gibson",
"Malcolm Tierney",
"Sandy Nelson",
"Sean Lawlor"
],
"starring.name": [
"Brendan Gleeson",
"Sophie Marceau",
"Mel Gibson",
"Patrick Mcgoohan",
"Catherine Mccormack"
]
}
maybe someone knows why the second title ... (in this case not sara bareilles as i said before, but) Hillary Weeks - who has a track called 'brave' ... why is it before title 'braveheart' and 'brave little toaster'?
EDIT AGAIN
to further complicate the situation, what if i had a 'rank' field that was a part of my document? i'm finding it very difficult to add that to my _score field using a script score function...
"functions": [
{
"script_score": {
"script": "_score * 1/ doc['rank'].value"
}
}
]