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