One of the most important selling tools you have for selling a house in Thailand is the internet. Through the internet you can reach millions potentially, although sometimes it is hard to get more than a handful of people to your site everyday.
That just got harder with the new changes this April to the Google Algorithm. The change seems to penalize those who try to boost there position in the SERPS. Those who don't regularly send links to there sites are unaffected; but those who were seeing good progress in their position in Google for keywords have, in many cases, seen the carpet pulled out from under their feet. Do not panic is the old seo wisdom - the site will be back. I'm not so sure. Some of my sites have been down for the longest time. If Google preferred genuine content above you, then you would have less reason to grumble; but often that is not the case. Here is what I'm more certain about:
Good original content
1) Google is trying to find a way mathematically to discern shit from shinola. The better you can write and the more originality and value you can add to your writing the more you will be rewarded both now and in the future with good SERPS position and Page Rank.
2) If you just continue sending backlinks to your site or sites then over time they will come back. The key is to hit a variety of key phrases. If you just keep linking 'property for sale in Thailand' then you will be forever penalized by Google. You must spread your links over lots of related keywords and phrases related to your niche. Variety.
3) The new (and not so new) idea in SEO is to fool Google by buying age and page rank. Every day valuable sites and URLs just get discontinued because someone lost interest or just plain forgot to renew their URL address. In auctions you can buy sites with 100s if not 1,000s of backlinks. You can find sites with page rank up to 5. If you buy a site with age it will soak up the links and will not be penalized so readily by Google. It may seem like starting again but you will be surprised how much difference age makes in the SERPS. You can also just move shop as it were, by redirecting your old site to your newly acquired aged domain.
Other Sources of Traffic
4) The final bit of advice is to find ways to not rely on Google. Lots of people make a good living from their sites and they are poorly placed in Google. How do they do this? The answer is through referrals. If you can get your links on sites with high traffic then you can see good traffic just from people clicking through to your site. The future is that more and more people will just pay for targeted traffic. Adwords is about this very topic.
You can make a sale. It is only a matter of time and hard work. The internet is only one way to sell your house. It is an important way no doubt and there is no reason to think that you cannot compete with 'the big boys'. The internet is a level playing field.