Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
toc sac » toc sach, hoc sach, doc sach
ky dang » ky nang, ky danh
dang xa » dang xay, lang xa, dang ha
han tai » hang tai, nhan tai, van tai
tuc va » thuc va, truc va, duc va
cuc te » cua te, cuc thue, cuc tieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sac) OR (toc san)) ky dang xa hoi. hieu van nam ((tuc va) or (tuc xa)) han tai cuc te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sac) OR (toc san)) ky dang xa hoi. hieu van nam ((tuc va) OR (tuc xa)) han tai cuc te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sac) OR (toc san)) ky dang xa hoi. hieu van nam ((tuc va) or (tuc xa)) han tai cuc te".
• Adding a wildcard symbol may retrieve word variants: ((toc sac) OR (toc san)) ky dang xa hoi. hieu van nam ((tuc va) or (tuc xa)) han tai cuc te*.