This is not what I am looking for.
Example: "I'm sorry, but that's not what I'm looking for. Do you perhaps also have checked shirts on offer?" Answer: "No, unfortunately we don't have that. You would have to ask in another shop."
Das ist nicht das, was ich suche. 
Det är inte vad jag letar efter. 
Det er ikke det jeg leder efter. 
Det er ikke hva jeg ser etter. 
Se ei ole mitä etsin. 
See ei ole see, mida ma otsin. 
Tai ne tai, ko aš ieškau. 
Tas nav tas, ko es meklēju. 
Þetta er ekki það sem ég er að leita að.