Perhaps you should try some spelling variations:
khanh hoa » thanh hoa
sach hoc » cach hoc, sach hoi, mach hoc
cuu dong » cuu cong, cuu tong, cuu long
hang hoa » hang khoa, thanh hoa, hang va
tan nhan » tran nhan, tao nhan, van nhan
nhan dan » phan dau, gian dan, nhan tai
tu sach » thu sach, su sach, te sach
hai tan » hai van, hai quan
hoc xa » hoc ma
xa hai » xa thai, xua hai, xa hoi

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 hoc tap, nghien cuu dong co ((khanh hoa) or (hang hoa)) hoc xa hai tan nhan dan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach hoc tap, nghien cuu dong co ((khanh hoa) OR (hang hoa)) hoc xa hai tan nhan dan.
• Adding a wildcard symbol may retrieve word variants: tu sach hoc tap, nghien cuu dong co ((khanh hoa) or (hang hoa)) hoc xa hai tan nhan dan*.