Perhaps you should try some spelling variations:
nhanh thai » nhanh thi, nhanh thanh, nhanh thang
hanh tai » thanh tai, hang tai, han tai
cua tre » cua te, cuu tre, cua triet
dang xa » dang xay, lang xa, dang va
dang ha » dong ha, dung ha, lang ha
hieu ve » hieu va, hieu van
cam duc » cam xuc, cao duc, pham duc
duc van » duc va, duc tan, duc manh
su sac » su sach, su cac, su xac
sac ky » cac ky, sai ky
ve cam » ve cham, ve cac, va cam

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

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