Perhaps you should try some spelling variations:
luong vat » luong va, luong van, luong tai
khoa hoi » khoan hoi, khoa hoc, khoa doi
cuu tre » cua tre, cau tren, cau treo
hanh de » hanh ve, hanh kem
hanh di » hanh vi, hang di, danh di
ve chat » va chat, van chat
hieu ve » hieu va, hieu van
hoa hoi » hoa hoc, hoa doi, hoc hoi
ky dung » ly dung, ky dang, ky vung
sai ky » sac ky
tu sai » tu bai, tu san, tu cai

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sai ky dung ((hoa hoi) or (khoa hoi)). hieu ve chat luong vat ((hanh di) OR (hanh de)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sai ky dung ((hoa hoi) OR (khoa hoi)). hieu ve chat luong vat ((hanh di) OR (hanh de)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sai ky dung ((hoa hoi) or (khoa hoi)). hieu ve chat luong vat ((hanh di) OR (hanh de)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu sai ky dung ((hoa hoi) or (khoa hoi)). hieu ve chat luong vat ((hanh di) OR (hanh de)) cuu tre*.