Duplicate content throughout multiple URLs dilemma

[versliukai]

We have a website with lots of categories and there are problems that some subcategories have identical content on them.

So, is it enough to just add different text on those problematic subcategories or we need to use "canonical" tag to main category.

Same dilemma is with our search system and duplicate content. For example, "/category/sports" URL would have similar to identical content with "/search/sports" and "/search/sports-fitness/" URLs.

Ranking factors is important for all different categories and subcategories. Ranking factors is also important for search individual keywords. So, the question is, how to make them somehow unique/different to rank on all those pages well?

Would love to hear advices how it can be solved using different methods and how it would affect our rankings. When we actually need to use "canonical" tag and when 301 redirect is better. Thanks!

[TammyWood]

Commonly on large ecommerce websites duplication between categories and sub categories is an issue. The views of search results can also be a factor IE: grid, list, etc-

Association the sub categories with the main top level categories by using the canonical tag. It is also a possibility to block the /search/ results by using the robots.txt- search results aren't the most beneficial to the user and this is a ranking factor.

The canonical tags are exceptionally effective for ecommerce structures.