Perhaps you should try some spelling variations:
"data using java snippets" » "data using data snippets"
"dang van cong snippets" » "hoang van cong snippets", "hang va cong snippets", "dang van dong snippets", "dang van phong snippets", "dang phan cong snippets"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code snippets", "locating bug core 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 van cong snippets") or ("data using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dang van cong snippets") OR ("data using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dang van cong snippets ) or ( data using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dang van cong snippets") or ("data using java snippets"))) or ("locating bug code snippets"))*.