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