public Query containsEquiv(List<String> values) {
        if (values.isEmpty()) {
            throw new IllegalArgumentException("value of \"contains equiv\" should not be empty");
        } else if (values.size() == 1) {
            // Vespa does not support one element equiv syntax, use contains instead
            return contains(values.get(0));
        } else {
            return common("equiv", annotation, values);
        }
    }
Contains equiv query.
https://docs.vespa.ai/en/reference/query-language-reference.html#contains

@param values the values
@return the query
client/src/main/java/ai/vespa/client/dsl/Field.java