I have launched my site www.gshbooster.com about 2 months ago, since
its inception, it has been listed on the first page of the taiwan
google when I typed in HMS90 or HMS-90 as my keywords. About two weeks
ago, I have noticed www.gshbooster.com has disappeared completely from
google and as well as yahoo unless I typed in gshbooster as my keyword.

My site is created with PHP and MySQL, most of my contents are
generated dynamically other than the index page where the contents are
hardcoded.

I would like to know what went wrong and how can I get google to index my
site again. Thanks.

Google refreshes everything about once a month. It's popularly called
"Google Dance". It might have removed you from the search. It ideally
should depend upon how many people have indexed you, and not the
technology/scripting you are using.

thanks sui-ga for your comment. What kind of "tricks" can I use so
other people will index me including google. Each of my page consists
of header/footer include files, and I have initiate session on top of
each page. Would that be the reason why google is not indexing my
page? Should I just create a static index page instead?

The "google dance" truly freaks me out. I just search google again and
my site is once again ranked on the first page of taiwan google with
keyword "HMS90" or "HMS-90". And it also showed all the related pages.
I hope this will retain and my site will no disappear again in google.
I am going to close the question for now. thanks for viewing this
thread.