Perhaps you should try some spelling variations:
"dong trien code slippers" » "dong trien cong slippers", "dong trien con slippers", "dong trieu code slippers", "dong tien code slippers", "dong tren code slippers"
"dung java java snippets" » "dung va java snippets"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code 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: (((("dung java java snippets") or ("dong trien code slippers"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dung java java snippets") OR ("dong trien code slippers"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung java java snippets ) or ( dong trien code slippers ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung java java snippets") or ("dong trien code slippers"))) or ("locating bug code snippets"))*.