Perhaps you should try some spelling variations:
nang cau » nang cao, hang cau, nang dau
hieu van » hieu va, thien van
cam thuc » am thuc, nam thuc, cam thu
thuc van » thuc vat, thuc dan, thuc va
van hanh » van thanh, ban hanh, van anh
hieu ve » hieu va
luu tre » luu tru, cuu tre, luy tre
te sac » te sach, te cac, te san
sac ky » cac ky, sai ky
vi luu » vi lua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te sac ky nang cau hoi. ((((hieu van) or (hieu ve))) or (lieu va)) cam thuc van hanh vi luu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky nang cau hoi. ((((hieu van) OR (hieu ve))) OR (lieu va)) cam thuc van hanh vi luu tre.
• Adding a wildcard symbol may retrieve word variants: te sac ky nang cau hoi. ((((hieu van) or (hieu ve))) or (lieu va)) cam thuc van hanh vi luu tre*.