Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
cua tre » cua te, cuu tre, cua triet
va hanh » van hanh, va thanh, va danh
hoa hoi » khoa hoi, hoa hoc, hoa doi
hieu va » lieu va, hieu qua
cam tuc » cam xuc, cam tu, dam thuc
vi cua » vai cua, di cua
su cac » tu cac, su cao, su can
ha hoi » ha noi, xa hoi, va hoi

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

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