Perhaps you should try some spelling variations:
"dong tinh doc snippets" » "dong kinh doc snippets", "dong tin doc snippets", "cong tinh doc snippets", "dong trinh doc snippets", "dong tinh hoc snippets", "dong tinh doi 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: (((("dong tinh doc snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dong tinh doc snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dong tinh doc snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dong tinh doc snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.