Google Earth's street-level address search is currently limited to the United States, United Kingdom, and Canada. Despite this, the search for addresses is not absolutely accurate.

Addresses are matched up with an exact position on the earth. Google Earth relies on a technique called "address interpolation", which is nothing but a fancy way of saying that it makes an educated guess.

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It takes the total number of addresses in a given city block and assumes an even distribution of the addresses along that block. Naturally, the results may not be always accurate. This happens since there does not seem to be any database support system that can accurately and precisely pinpoint street addresses.
As a workaround, you can try entering the nearest intersection of roads into Google Earth's 'street address' field, in addition to your city/state/zipcode, and locate your address from there