Perhaps you should try some spelling variations:
hoa khanh » hoa thanh, hoa phan, hoa hinh
thu sach » tu sach, thuat sach, thuoc sach
sach hoc » cach hoc, sach hoi, mach hoc
cuu dong » cuu cong, cuu tong, cuu long
van nhan » van phan, van thanh, danh nhan
nhan dan » phan dau, gian dan, nhan tai
o khanh » _ khanh, le khanh, vu khanh
hoi van » hoi va, hoi dan, hai van
hoc xa » hoc ma

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach hoc tap, nghien cuu dong ((o khanh) OR (hoa khanh)) hoa hoc xa hoi van nhan dan~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach hoc tap, nghien cuu dong ((o khanh) OR (hoa khanh)) hoa hoc xa hoi van nhan dan".
• Adding a wildcard symbol may retrieve word variants: thu sach hoc tap, nghien cuu dong ((o khanh) OR (hoa khanh)) hoa hoc xa hoi van nhan dan*.