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