Perhaps you should try some spelling variations:
tai khoa » da khoa, noi khoa
hanh hai » thanh hai, nhanh hai, hang hai
ban hanh » ban hang
cua tre » cua te, cuu tre, cua triet
hai cua » thai cua, dai cua, hoi cua
tang xa » trang xa, tang ma, lang xa
sai kho » dai kho, dai khoa, mai khoa
dua ban » dia ban, cua ban, qua ban
va cam » va cham, va cac, va cao
ve cam » ve cham, ve cac, ve cai

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 kho) OR (tai khoa)) tang xa hoi. hieu ((ve cam) or (va cam)) dua ban hanh hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sai kho) OR (tai khoa)) tang xa hoi. hieu ((ve cam) OR (va cam)) dua ban hanh hai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sai kho) OR (tai khoa)) tang xa hoi. hieu ((ve cam) or (va cam)) dua ban hanh hai cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((sai kho) OR (tai khoa)) tang xa hoi. hieu ((ve cam) or (va cam)) dua ban hanh hai cua tre*.