String Matching in an Array

Problem statement

Given an array of string words. Return all strings in words which is substring of another word in any order. 

String words[i] is substring of words[j], if can be obtained removing some characters to left and/or right side of words[j].

Example 1:

Input: words = ["mass","as","hero","superhero"]Output: ["as","hero"]Explanation: "as" is substring of "mass" and "hero" is substring of "superhero".["hero","as"] is also a valid answer.

Example 2:

Input: words = ["leetcode","et","code"]Output: ["et","code"]Explanation: "et", "code" are substring of "leetcode".

Example 3:

Input: words = ["blue","green","bu"]Output: []

Constraints:

• 1 <= words.length <= 100
• 1 <= words[i].length <= 30
• words[i] contains only lowercase English letters.
• It's guaranteed that words[i] will be unique.

My solution

/**
 * @param {string[]} words
 * @return {string[]}
 */
var stringMatching = function(words) {
    const track = {};
    
    for (let i = 0; i < words.length; i++) {
        for (let j = 0; j < words.length; j++) {
            // console.log(i, j)
            const ref = words[i].length < words[j].length ? words[i]: words[j]
            const search = words[i].length > words[j].length ? words[i]: words[j]
            if (ref === search || track[ref]) {
                continue;
            }
            
            // console.log(ref, search);
            
            if (search.indexOf(ref) > -1) {
                if (!track[ref]) {
                    track[ref] = [search]
                } else {
                    track[ref].push(search)
                }
            }
        }
    }
    
    // console.log(track)
    
    return Object.keys(track)
};