Perhaps you should try some spelling variations:
"danh hoc chat snippets" » "danh hoc code snippets", "dan hoc chat snippets", "danh hoa chat snippets", "anh hoc chat snippets", "danh hoc phat snippets", "danh hoc cao snippets", "danh hoc phan snippets"
"locating bug core snippets" » "locating bug code snippets"
"dung java java snippets" » "dung va java 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: (((("danh hoc chat snippets") or ("dung java java snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("danh hoc chat snippets") OR ("dung java java snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( danh hoc chat snippets ) or ( dung java java snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("danh hoc chat snippets") or ("dung java java snippets"))) or ("locating bug core snippets"))*.