Perhaps you should try some spelling variations:
danh doi » danh di, thanh doi, dung doi
trung va » truong va, trang va, trung ha
hieu van » hieu va, thien van, lieu va
truc va » thuc va, thuc vat
doi cua » dai cua, hoi cua
van cau » van dau, van hau, van chat
sach ky » sach y, sach ty, sach kem
nang ma » tang ma, sang ma, nang cao
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
sac ky » cac ky, sai ky

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

• If you are trying to use Boolean operators, they must be ALL CAPS: thuat ((sach ky) OR (sac ky)) nang ma hoi. hieu van cau ((truc va) OR (trung va)) danh doi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat ((sach ky) OR (sac ky)) nang ma hoi. hieu van cau ((truc va) or (trung va)) danh doi cua tre~".
• Adding a wildcard symbol may retrieve word variants: thuat ((sach ky) OR (sac ky)) nang ma hoi. hieu van cau ((truc va) or (trung va)) danh doi cua tre*.