Perhaps you should try some spelling variations:
"implement retinex algorithm" » "implement cosine algorithm" (Expand Search)
"level coding algorithm" » "level cosine algorithm" (Expand Search), "level colony algorithm" (Expand Search), "level scheduling algorithm" (Expand Search)
"element mean algorithm" » "element deer algorithm" (Expand Search), "element search algorithm" (Expand Search), "elements mean algorithm" (Expand Search)

Try widening your search to All Fields.

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• Performing a fuzzy search may retrieve terms with similar spellings: (("element mean algorithm") OR ((("implement retinex algorithm") OR ("level coding algorithm"))))~.
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• Removing quotes may allow a broader search: (( element mean algorithm ) OR ((( implement retinex algorithm ) OR ( level coding algorithm )))).
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