Perhaps you should try some spelling variations:
tac thuoc » tao thuoc, truc thuoc, tac thuong
bac tuoc » bach tuoc, bac hoc, bac tu
su sach » so sach, vu sach
thi van » thi lan, thi hanh, thi nang
tinh da » tinh va, tinh gia, tinh lao
nang xa » nang x, lang xa, nang ma
so sanh » do sanh
cuu tre » cua tre, cau tren, cau treo
v nang » va nang, vu nang, van nang
da cuu » da cau, da cu, da cua

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) or (so sanh)) v nang xa hoi. thi van ((bac tuoc) OR (tac thuoc)) may tinh da cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sanh)) v nang xa hoi. thi van ((bac tuoc) OR (tac thuoc)) may tinh da cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (so sanh)) v nang xa hoi. thi van ((bac tuoc) OR (tac thuoc)) may tinh da cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (so sanh)) v nang xa hoi. thi van ((bac tuoc) OR (tac thuoc)) may tinh da cuu tre*.