Siberian 13 Junior Poster

How can I do a deep system search for files ?
Windows default indexer scans only at a surface level, missing alot of files. For example, if I search for all text files, it will find 35-40% and skip the rest. I want it to find all 100% of the text files on my computer and shared networked drives. I tried 3rd party file managers and they also only scanned 35-40%, is there no way to scan 100% and look in every folder / sub-folder on the PC ?