Yahoo's site: usage

yahoo search, site: usage, indexing, serps

[jive01]

Typing in site:www.domain.tld or site:domain.tld shows up indexed pages of a site.

For 1 site I have, I use the above syntax and I get just the home page returned - leading me to believe this is the only page indexed.

However, using site:http://www.domain.tld, I get a few hundred pages showing up. What's going on here?

Searching for 'exact' text chunks/titles etc should bring these other pages up in the results - yet no matter what - no page (other than the home page) can be retrieved via a search.

Site background: 420 pages, fully indexed by Google, up and running for 6 months. The site gets no referrals at all from Yahoo. The site shouldn't have any penalties at all, no duplicate content issues and so on.

Any ideas on this?

Thanks