Perhaps you should try some spelling variations:
hanh thai » nhanh thai, hinh thai, hanh tai
thai cua » than cua, tai cuc, tri cua
van hanh » van thanh, ban hanh, van anh
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
lang xa » dang xay, lang van
duc van » duc va, duc tan, duc manh
cam duc » cam xuc, cao duc, pham duc
lang ha » long ha
ve cam » ve cham, ve cac, va cam
dai ky » dan ky, dai ly
sai ky » sac ky

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

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