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