Perhaps you should try some spelling variations:
"python missing data snippets" » "python using data snippets"
"khu du doc snippets" » "khu do doc snippets", "khu duy doc snippets", "khu du hoc snippets", "khu nu doc 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: (((("khu du doc snippets") or ("python missing data snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("khu du doc snippets") OR ("python missing data snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( khu du doc snippets ) or ( python missing data snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("khu du doc snippets") or ("python missing data snippets"))) or ("locating bug code snippets"))*.