Total Commander

Auto-complete and Auto-append in "Search in:" field of Find Files will make it faster to manually enter several search locations using following scenario:
1) start entering path 1 (e.g. c:\dir1\) by entering first path characters, use auto-append or auto-complete to choose it;
1.1) add semicolon (;) to it and cut to Clipboard;
2) start entering path (e.g. d:\dir2) by entering first path characters, use auto-append or auto-complete to choose it;
2.1) add semicolon (;) to it;
2.2) paste previously copied path from clipboard after semicolon;
2.2) select everything in Search in field, cut to Clipboard again;
3) and so on until all search locations are in Search in: field.

This solution uses reversed logic: If you suspect that the file is most likely in some specific directory, you should enter this location as the last one and add all previously selected locations after semicolon.
You can use notepad to copy and add directories in a normal order (starting from most expected location) rather than reversed one.