Perhaps you should try some spelling variations:
thanh thai » thanh hai, thanh tai, nhanh thai
cua triet » cua viet, su triet, va triet
van thanh » ban thanh, van tuan
cua tre » cua te, cuu tre, dua tren
duc van » duc va, duc tan, duc manh
cao duc » dao duc, cao suc, giao duc
hieu ve » hieu va, hieu van
tang ha » lang ha, tang ma, trung ha
dung ha » dung va, dung he, dung khoa
tai ky » thai ky, trai ky, sai ky
ve cao » va cao, ve bao, ve cac
su tai » su thi, tu tai

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 ky ((tang ha) or (dung ha)) hoi. hieu ve cao duc van thanh thai ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su tai ky ((tang ha) OR (dung ha)) hoi. hieu ve cao duc van thanh thai ((cua tre) OR (cua triet)).
• Adding a wildcard symbol may retrieve word variants: su tai ky ((tang ha) or (dung ha)) hoi. hieu ve cao duc van thanh thai ((cua tre) or (cua triet))*.