Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van cau » van dau, van hau, van chat
cuu tre » cua tre, cau tren, cau treo
dang ha » dong ha, dung ha, lang ha
dang xa » dang xay, lang xa, dang va
sac ky » cac ky, sai ky
vi cuu » vi luu, vinh cuu
su sac » su sach, su cac, su xac

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 van cau ((duc va) or (tuc xa)) hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ky ((dang xa) OR (dang ha)) hoi. hieu van cau ((duc va) OR (tuc xa)) hanh vi cuu tre.
• Adding a wildcard symbol may retrieve word variants: su sac ky ((dang xa) or (dang ha)) hoi. hieu van cau ((duc va) or (tuc xa)) hanh vi cuu tre*.