Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thanh de » hanh de, thanh ve, thanh do
thuc dan » thuc hanh, hoc dan
su sach » vu sach
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
so sach » so sanh, bo sach, co sach
de cua » le cua, te cua, dieu cua
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) OR (so sach)) ty nang xa hoi. hieu van nam ((thuc dan) or (thuc vat)) thanh de cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sach)) ty nang xa hoi. hieu van nam ((thuc dan) OR (thuc vat)) thanh de cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) OR (so sach)) ty nang xa hoi. hieu van nam ((thuc dan) or (thuc vat)) thanh de cua te".
• Adding a wildcard symbol may retrieve word variants: ((su sach) OR (so sach)) ty nang xa hoi. hieu van nam ((thuc dan) or (thuc vat)) thanh de cua te*.