Perhaps you should try some spelling variations:
"dang tran chap snippets" » "dang tran code snippets", "dang thanh chap snippets", "quang tran chap snippets", "hoang tran chap snippets", "dang tranh chap snippets", "dang tran chau snippets", "dang trang cham 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 chap 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 chap snippets") OR ("dung java java snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( dang tran chap snippets ) or ( dung java java snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dang tran chap snippets") or ("dung java java snippets"))) or ("locating bug core snippets"))*.