Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
dan hanh » dang hanh, dan khanh, dan thanh
sach ky » sach ty, sach kem, sach hay
nang xa » nang x, lang xa, nang ma
van cuu » van cau, van chu, van cu
cuu hoc » cua hoc, cuu thuoc, cuu khoa
hanh ve » hanh vi, hanh va, hanh kem
sac ky » cac ky, sai ky
ve cua » le cua, de cua, te 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) OR (sac ky))) or (sach y)) nang xa hoi. hieu van cuu hoc dan hanh ve cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((((sach ky) OR (sac ky))) OR (sach y)) nang xa hoi. hieu van cuu hoc dan hanh ve cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((((sach ky) OR (sac ky))) or (sach y)) nang xa hoi. hieu van cuu hoc dan hanh ve cua te".
• Adding a wildcard symbol may retrieve word variants: tu ((((sach ky) OR (sac ky))) or (sach y)) nang xa hoi. hieu van cuu hoc dan hanh ve cua te*.