If you have any document in a format that your text processor can't open, try out TextMaker Viewer. This application can open a wide range of formats: DOCX, DOC, SXW RTF, PSW, DOT, PWD, HTML, ODT, or TXT. Furthermore, it also allows you to open TMD documents, that are native to the TextMaker word processor.
TextMaker Viewer will allow you to view documents, carry out searches, print and even export them to PDF. Even though it doesn't allow you to edit texts, it will be very useful to open files without having to install all the required applications.