Perhaps you should try some spelling variations:
hinh thai » sinh thai, tinh thai, dinh thi
hanh thai » nhanh thai, hanh tai, anh thai
hieu van » hieu va, thien van, lieu va
cua tre » cua te, cuu tre, cua triet
cam duc » cam xuc, cao duc, pham duc
duc van » duc va, duc tan, duc manh
tang xa » trang xa, tang ma, lang xa
hieu ve » hieu va
ky tang » ky nang, ky dang, kho tang
sac ky » cac ky, sai ky
su sac » su sach, su cac, su xac

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sac ky tang xa hoi. ((hieu ve) OR (hieu van)) cam duc van ((hanh thai) or (hinh thai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ky tang xa hoi. ((hieu ve) OR (hieu van)) cam duc van ((hanh thai) OR (hinh thai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sac ky tang xa hoi. ((hieu ve) OR (hieu van)) cam duc van ((hanh thai) or (hinh thai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: su sac ky tang xa hoi. ((hieu ve) OR (hieu van)) cam duc van ((hanh thai) or (hinh thai)) cua tre*.