如何在golang的elasticsearch文档（索引）中搜索字符串？

我正在用 golang 编写一个函数来搜索已编入索引的 elasticsearch 文档中的字符串。我正在使用 elasticsearch golang 客户端elastic。例如考虑对象是推文，

type Tweet struct {

    User    string

    Message string

    Retweets int

}

搜索功能是

func SearchProject() error{

    // Search with a term query

    termQuery := elastic.NewTermQuery("user", "olivere")

    searchResult, err := client.Search().

        Index("twitter").   // search in index "twitter"

        Query(&termQuery).  // specify the query

        Sort("user", true). // sort by "user" field, ascending

        From(0).Size(10).   // take documents 0-9

        Pretty(true).       // pretty print request and response JSON

        Do()                // execute

    if err != nil {

        // Handle error

        panic(err)

        return err

    }

    // searchResult is of type SearchResult and returns hits, suggestions,

    // and all kinds of other information from Elasticsearch.

    fmt.Printf("Query took %d milliseconds\n", searchResult.TookInMillis)

    // Each is a convenience function that iterates over hits in a search result.

    // It makes sure you don't need to check for nil values in the response.

    // However, it ignores errors in serialization. If you want full control

    // over iterating the hits, see below.

    var ttyp Tweet

    for _, item := range searchResult.Each(reflect.TypeOf(ttyp)) {

        t := item.(Tweet)

        fmt.Printf("Tweet by %s: %s\n", t.User, t.Message)

    }

此搜索正在打印用户“olivere”的推文。但是如果我给出“橄榄”，那么搜索就不起作用了。如何搜索属于用户/消息/转推的字符串？

有人可以帮我解决这个问题吗？谢谢