Oh man, thanks for posting all these.
I was experiencing the same issue in trying to import a chinese language Word document. I was losing all my bolds. I tried many different things: saving in different file formats and variations of Word (someone suggested RTF files work), tried different fonts in Word, different import settings in Indesign but all failed to retain my Bolds.
Finally I discovered (mainly through reading this thread) that the issue lied in the author having used the ‘B’ and ‘I’ buttons in Word to add Bold and Italic formatting, rather than using the actual Bold or Italic variations of the font.
Here’s how I fixed it:
I did an advanced search and replace in MS Word by:
– Searching for ‘Format: Font: Font Style: Bold’ (leaving all other fields blank)
– And replacing with ‘Font: Source Han Serif SC Heavy (fill in your own here, bold/italic), Not Bold’.
This last part of ‘Not Bold’ is the ‘font style’ field in the ‘Font Search and Replace menu’. This takes off the Bold applied by the MS Word ‘B’ formatting button but by choosing to replace it with the ‘Heavy Font variation’ it retains the proper formatting.