Expand_keywords and BuildExcerpts

I have an index with expand_keywords=1, search with part-of-word queries works perfectly fine, but when I try to make excerpts with the same query BuildExcerpts doesn’t highlight anything. For example, document:

Number one

Can be found with query “numb”, but creating excerpts for it with the same query “numb” returns unchanged original text.

Is there any way to successfully build excerpts in this case?

What options do you have set for BuildExcerpts? is query_mode enabled?

I added query_mode=true, but it didn’t help

here is my setup:


index test
    source              = test

    path                = /var/lib/sphinx/data/test

    type                = plain
    docinfo             = extern
    charset_type        = utf-8
    morphology          = libstemmer_en, libstemmer_ru
    min_infix_len      = 3
    expand_keywords     = 1
    index_exact_words   = 1
    enable_star         = 1
    ngram_len           = 1

Code in JS that builds excerpts(using this client lib https://github.com/Inist-CNRS/node-sphinxapi):

let excerpts = await client.BuildExcerptsAsync(['Number one'], 'test', 'numb', {
  before_match: '|||',
  after_match: '|||',
  html_strip_mode: 'strip',
  query_mode: true
console.log(excerpts) // prints [ 'Number one' ]