Perhaps you should try some spelling variations:
dieu hien » dieu khien, dieu kien, bieu hien
hanh thai » nhanh thai, hinh thai, hanh tai
thai cao » thoai cac, thuat cao, toan cao
hien cac » thien cac, vien cac, hieu cac
thai cua » than cua, tai cuc, tri cua
tai cao » tao cao, tai sao, tai cac
tang xa » trang xa, tang ma, lang xa
duc van » duc tan, duc manh, duc phan
cua tre » cua te, cuu tre, cua triet

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

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