I have the following question:

I still have a valid Non immigrant type O multiple entry ( married to a Thai)

date of issue: 20-12-2011 ( Savannakhet Laos)

entry 1: 21-12-2011 from Laos

entry 2: 15-03-2012 from Singapore

So it is stiil good for 2 more 3 months entries.

In June i will be going to Holland for visit family and friends and i thought when i'm there why not get a new visum at the Thai embassy in The Hague ( got one there before) it would save me a trip to Laos later on this year.

Is that possible? getting ( applying) a new visum while still having a valid one??

So i first use the "old" one ( 2 more entries) and then starting with the "new" one. ( between the time of issue and enter before, is one year)

Anyone did this before ?? if yes, having trouble at the airport having 2 valid visa ??

Thanks in advance.

The Embassy will simply cancel the current visa before issueing a new one. So you will lose more than half a year on the old visa. Not very economical.