I think it would be better if you explained what you're trying to do. Your first post said you wanted to find and replace some text within a Microsoft Word document. If your goal is to use some sort of template and customise it per user/customer then there are alternatives to Microsoft word. For example PDF::Reuse (see also PDF::Reuse::Tutorial). If the problem you're trying to solve is something other than this please let us know.

I am a pre-sales technical support engineer. Nearly everyday a lot of sales call me to provide product-combination and related price. I use Perl to create a CGI page to meet the requirement. By Perl, Excel has already been created automatically, while how to get the report(used to be Word format) is my question. PS， the WORD report is based on some templates, so what I need to do is find and replace some key strings.

Sorry for the delay in my reply. Using a Microsoft word based template limits your options when working under Linux. If it would be possible to recreate your template in another format this could make the task easier for you. As previously mentioned, a PDF based solution, more research on the word format or automating a tool like Open/Libre office.