Perhaps you should try some spelling variations:
hieu quan » lieu quan, thien quan, lien quan
va hanh » van hanh, va thanh, va danh
thai do » thay doi, thai den
ky lang » ky nang, ky dang, ky tang
cuu tre » cua tre, cau tren, cau treo
hoa hoi » khoa hoi, hoa hoc, hoa doi
ha hoi » ha noi, xa hoi, va hoi
vi cuu » vi luu, vinh cuu
te cac » tu cac, ve cac, te cao
do va » do van, so va

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

• Performing a fuzzy search may retrieve terms with similar spellings: te cac ky lang ((ha hoi) OR (hoa hoi)). ((hieu quan) or (hieu qua)) thai do va hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te cac ky lang ((ha hoi) OR (hoa hoi)). ((hieu quan) OR (hieu qua)) thai do va hanh vi cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te cac ky lang ((ha hoi) OR (hoa hoi)). ((hieu quan) or (hieu qua)) thai do va hanh vi cuu tre".
• Adding a wildcard symbol may retrieve word variants: te cac ky lang ((ha hoi) OR (hoa hoi)). ((hieu quan) or (hieu qua)) thai do va hanh vi cuu tre*.