Perhaps you should try some spelling variations:
"don thuoc co snippets" » "dong thuoc co snippets", "dung thuoc co snippets", "dang thuoc co snippets", "don thuc co snippets", "don thuoc bo snippets", "don thuoc ho 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: (((("don thuoc co snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("don thuoc co snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( don thuoc co snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("don thuoc co snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.