Perhaps you should try some spelling variations:
"data using java snippets" » "data using data snippets", "data using java slippers"
"cong trinh van snippets" » "cong trinh han snippets", "cong trinh quan snippets", "cong trinh toan snippets", "cong trinh van slippers"
"locating bug code snippets" » "locating bug code slippers", "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: (((("cong trinh van snippets") or ("data using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("cong trinh van snippets") OR ("data using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( cong trinh van snippets ) or ( data using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("cong trinh van snippets") or ("data using java snippets"))) or ("locating bug code snippets"))*.