Perhaps you should try some spelling variations:
"dang tran hoan snippets" » "dang tran code snippets", "dang thanh hoan snippets", "quang tran hoan snippets", "hoang tran hoan snippets", "dang tran hoang snippets", "dang tuan hoan snippets", "dang tran doan 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: (((("dang tran hoan snippets") or ("dung java java snippets"))) or ("locating bug core snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dang tran hoan snippets") OR ("dung java java snippets"))) OR ("locating bug core snippets")).
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