Perhaps you should try some spelling variations:
"locating bug core snippets" » "locating bug code snippets"
"dang trinh luan snippets" » "dang tinh luan snippets", "dan trinh luan snippets", "dong trinh luan snippets", "dang trinh luat snippets", "dang trinh quan snippets", "dang trinh han 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 trinh luan 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 trinh luan snippets") OR ("dung java java snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( dang trinh luan snippets ) or ( dung java java snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dang trinh luan snippets") or ("dung java java snippets"))) or ("locating bug core snippets"))*.