Perhaps you should try some spelling variations:
thien hach » thien thanh
hien hanh » dieu hanh
sach ky » sac ky, sach y, sach ty
tuoc va » thuoc va, nuoc va, duoc va
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
cuu tre » cua tre, cau tren, cau treo
dan du » dan dau, danh du, van du
dan su » dang su

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 nang xa hoi. hieu ((hien hanh) or (thien hach)) tuoc va ((dan du) OR (dan su)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang xa hoi. hieu ((hien hanh) OR (thien hach)) tuoc va ((dan du) OR (dan su)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang xa hoi. hieu ((hien hanh) or (thien hach)) tuoc va ((dan du) OR (dan su)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang xa hoi. hieu ((hien hanh) or (thien hach)) tuoc va ((dan du) OR (dan su)) cuu tre*.