Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
dang xay » dang van, van xay
manh hai » minh hai, thanh hai, van hai
hieu van » hieu va, thien van, lieu va
lanh hai » thanh hai, lang chai, lanh dao
su sach » so sach, vu sach
duc ban » duc tan, duc van, dua ban
sach ky » sac ky, sach y, sach ty
van cac » van hac, van cau, van bac
xay hoi » xa hoi, tay hoi, cay phoi
ky dang » ky nang, ky danh
cac duc » cac du, cao duc, cac dac

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 ky dang xay hoi. hieu van cac duc ban ((lanh hai) or (manh hai)) cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky dang xay hoi. hieu van cac duc ban ((lanh hai) OR (manh hai)) cua viet.
• Adding a wildcard symbol may retrieve word variants: su sach ky dang xay hoi. hieu van cac duc ban ((lanh hai) or (manh hai)) cua viet*.