<form method="post" ng-submit="find()" name="findForm">

   <div class="form-group">
       <input class="form-control input-lg" type="text" name="word"
           ng-model="word" placeholder="search from Mongo" >
   </div>

   <button type="submit" class="btn btn-lg btn-block btn-success">search
   </button>

angular.module('MyApp')
.controller('SearchCtrl', ['$scope', '$http', function($scope, $http) {
    $http.post('/api/search', $scope.word)
    $scope.search= function() {
        ({
            -----??
        });
    };
}]);

app.post('/api/search', function(req, res) {
   Word.find(........)
// here I dont know how ..

});

$scope.find = function() {
      $http.post('/api/search', $scope.word).then(function(response) {
        $scope.words = response.data;
        //your code
      });
};

app.post('/api/search', function(req, res) {
      var query = {};
      //generetae query for partial search
      query.word = new RegExp(req.body.word, 'i');// assume word is field name for query.word

        Word.find(query, function(error, words){
          if(error) {
            return res.status(400).send({msg:"error occurred"});
          }
          return res.status(200).send(words);
        });
   });

angular.module('SymText')
  .controller('FreeWrtCtrl', ['$scope', '$http', function ($scope, $http) {

    $scope.find = function () {
        $http.post('/api/find',$scope.word)
            .then(function (response) {
                $scope.words = response.data;

        })
    }

}]);

app.post('/api/find', function (req, res) {

var query={};
query.word=new RegExp(req.body.word, 'i');

//console.log(req.body.word);
User.find(query, function (err, words) {
        if (err) return res.status(400).send({msg:" error during search DB"});
        console.log(words);
        return res.status(200).send(words);

    }
)

var userSchema = new mongoose.Schema({
    username: {type: String, unique: true, required: true},
    password: {type: String, required: true},
    fullname: {type: String, required: true},
    role: Number
});