Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thuc dan » thuc hanh, thuc vat
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
van cuu » van cau, van chu, van cu
hanh tu » anh tu, danh tu
tu cua » hu cua, vu 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: tu sach ky nang xa hoi. hieu van cuu ((thuc dan) OR (hoc dan)) hanh tu cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang xa hoi. hieu van cuu ((thuc dan) OR (hoc dan)) hanh tu cua te".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. hieu van cuu ((thuc dan) OR (hoc dan)) hanh tu cua te*.