Perhaps you should try some spelling variations:
hinh thai » sinh thai, tinh thai, dinh thi
thai cua » than cua, tai cuc, tri cua
duc manh » suc manh, duc anh, duc minh
cua tre » cua te, cuu tre, cua triet
duc van » duc va, duc tan, duc phan
hieu ve » hieu va, hieu van
dang xa » dang xay, lang xa, dang ha
ky dang » ky nang, ky danh
ve cam » ve cham, ve cac, va cam
su tai » su thi, tu tai
su sai » su hai, su dai, su mai

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

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