Perhaps you should try some spelling variations:
thuat sach » thuat san
thuat lanh » thuat lap, thuat san
ban hanh » ban hang
va tham » van tham, va cham, va thanh
lang xa » lang ha, dang xay, lang van
ty lang » tay lang, ty xang, ty hang
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thuat sach) OR (thuat lanh)) ty lang xa hoi. hieu ((ve cam) or (va tham)) cua ban hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thuat sach) OR (thuat lanh)) ty lang xa hoi. hieu ((ve cam) OR (va tham)) cua ban hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thuat sach) OR (thuat lanh)) ty lang xa hoi. hieu ((ve cam) or (va tham)) cua ban hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((thuat sach) OR (thuat lanh)) ty lang xa hoi. hieu ((ve cam) or (va tham)) cua ban hanh vi cua tre*.