Perhaps you should try some spelling variations:
manh hanh » xanh hanh, danh thanh, minh thanh
hanh loai » thanh hoai, thanh loan, phan loai
hieu van » thien van, hieu ve
duc manh » suc manh, duc anh, duc minh
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
hieu va » hieu qua
loai ca » loai cay, loai cua, loai va
ca viet » va viet, co viet, hoa viet
x hoi » xa hoi, o hoi, x ho

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 ty nang x hoi. ((((hieu van) or (hieu va))) or (lieu va)) pham duc manh hanh loai ca viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty nang x hoi. ((((hieu van) OR (hieu va))) OR (lieu va)) pham duc manh hanh loai ca viet.
• Adding a wildcard symbol may retrieve word variants: su sach ty nang x hoi. ((((hieu van) or (hieu va))) or (lieu va)) pham duc manh hanh loai ca viet*.