Perhaps you should try some spelling variations:
"duong hoc chat snippets" » "dong hoc chat snippets", "dung hoc chat snippets", "duong hoi chat snippets", "duong hoc phat snippets", "duong hoc cao snippets", "duong hoc phan snippets"
"dung java java snippets" » "dung va java snippets"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code snippets", "locating bug core snippets"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("duong hoc chat snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("duong hoc chat snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( duong hoc chat snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("duong hoc chat snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.