[help]searching the value without filtering

[kimteany]

hello...i would like to ask some opinion here...

how i want to search/detecting the value without filtering the data? currently i'm using double hashing to search the the value... 

for example: 

i have 1000 tags with the value and will transferred to the database.

however, the value considered missing when there are unable to detect the value which it is actually exist in the database..

collision could be happen within the value... 

so, i would like to read some opinion that possibly could help me to detect the missing value in fast way without filtering the data...

thanks...