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