Perhaps you should try some spelling variations:
"python missing data snippets" » "python using data snippets"
"locating bug core snippets" » "locating bug code snippets"
"ho duc dan snippets" » "ho duoc dan snippets", "ho duc tan snippets", "ho duc dai snippets", "hoc duc dan snippets", "do duc dan snippets", "hong duc dan snippets"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("ho duc dan snippets") OR ("python missing data snippets"))) OR ("locating bug core snippets"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"ho duc dan snippets\") OR (\"python missing data snippets\"))) OR (\"locating bug core snippets\"))".
• Removing quotes may allow a broader search: (((( ho duc dan snippets ) OR ( python missing data snippets ))) OR ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("ho duc dan snippets") OR ("python missing data snippets"))) OR ("locating bug core snippets"))*.