Understanding the Advanced Explanation in the Preview tab

Advanced Explanation

This section contains the fields searched against --> 0.0006530678 = (MATCH) custom(((sku:jacket | brandtext:jacket^11.0 | itemnametext:jacket | itemnameprefix:jacket | content:jacket | size-propertytext:jacket | size-propertyprefix:jacket)~0.1)~1, boost), product of:
- 0.0006530678 = custom score: product of:
  - 0.06576188 = (MATCH) sum of:
    - 0.06576188 = (MATCH) max plus 0.1 times others of:
      - Lines beginning with "(MATCH) weight" show which field is being matched, in this case "itemname" --> 0.06337103 = (MATCH) weight(itemnametext:jacket in 3147), product of:
        0.03547745 = queryWeight(itemnametext:jacket), product of:
        3.572468 = idf(docFreq=264, maxDocs=3471)
        0.009930796 = queryNorm
        1.786234 = (MATCH) fieldWeight(itemnametext:jacket in 3147), product of:
        1 = tf(termFreq(itemnametext:jacket)=1)
        3.572468 = idf(docFreq=264, maxDocs=3471)
        0.5 = fieldNorm(field=itemnametext, doc=3147)
      - Lines beginning with "(MATCH) weight" show which field is being matched, in this case "content" -->0.02390843 = (MATCH) weight(content:jacket in 3147), product of:
        0.02961947 = queryWeight(content:jacket), product of:
        2.982587 = idf(docFreq=477, maxDocs=3471)
        0.009930796 = queryNorm
        0.8071864 = (MATCH) fieldWeight(content:jacket in 3147), product of:
        3.464102 = tf(termFreq(content:jacket)=12)
        2.982587 = idf(docFreq=477, maxDocs=3471)
        0.078125 = fieldNorm(field=content, doc=3147)
  - 0.009930796 = (MATCH) boost, product of:
    - 1 = boost=1
    - 1 = boost
    - 0.009930796 = queryNorm
- 1 = queryBoost