Perhaps you should try some spelling variations:
"khanh toan de snippets" » "thanh toan de snippets", "khanh thanh de snippets", "khanh thuan de snippets", "khanh toan du snippets", "khanh toan ke snippets", "khanh toan ve 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: (((("khanh toan de snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("khanh toan de snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( khanh toan de snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("khanh toan de snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.