Perhaps you should try some spelling variations:
"implement routing algorithm" » "implement routine algorithm" (Expand Search), "implement modeling algorithm" (Expand Search), "implement finding algorithm" (Expand Search), "implement making algorithm" (Expand Search)
"level coding algorithm" » "level cosine algorithm" (Expand Search), "level modeling algorithm" (Expand Search), "level finding algorithm" (Expand Search), "level according algorithm" (Expand Search), "level using algorithm" (Expand Search)
"element tree algorithms" » "element three algorithms" (Expand Search), "element art algorithms" (Expand Search), "element two algorithms" (Expand Search), "element ree algorithms" (Expand Search), "element te algorithms" (Expand Search), "element ore algorithms" (Expand Search)

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: (((("implement routing algorithm") OR ("element tree algorithms"))) OR ("level coding algorithm"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"implement routing algorithm\") OR (\"element tree algorithms\"))) OR (\"level coding algorithm\"))".
• Removing quotes may allow a broader search: (((( implement routing algorithm ) OR ( element tree algorithms ))) OR ( level coding algorithm )).
• Adding a wildcard symbol may retrieve word variants: (((("implement routing algorithm") OR ("element tree algorithms"))) OR ("level coding algorithm"))*.