A Filipino teacher taught that "women are treated unequal"! Right or Wrong?

A Filipino teacher taught that "women are treated unequal". I think it should be "unequally".

Is there any structure "to treat someone adjective" in English?

Does "to treat me bad" make any sense?

Searching "treat her bad" & "treat her badly" on Google returns more than 50000 & 48000 results respectively

You want to describe how women are treated. It's an adverb that answers the question of how, when, or where, not an adjectives. So you should say:

Women are treated unequally.

By the way, there are special verbs that are followed by adjectives. Read about them here.

Google searches in the whole Web, which is not a reliable corpus to learn a language from. You can use a good dictionary with lots of examples, or if you like to find examples for yourself, you can use one of these corpora.
In this case, if you do search in the COCA, you'll find results like these (which are far from treating someone (un)equal):

• They are taught to treat all people with equal respect.
• You will long for him to treat you as an equal.
• ... by telling them that they have to treat women like equal and ...
• I have to treat her like an equal.

In the same way you shouldn't say "to treat someone bad". Then again, in an informal style speakers sometimes use adjectives instead of adverbs. This is one of the many rules that some people bend to speak in a more relaxed and casual way. You can read about that here.

And, you can read about predicative adjuncts under this question. This is another case where you can have an adjective after a verb, but that is not the case here. Because here you want to describe the action (to treat), not the object (women).