Perhaps you should try some spelling variations:
thien hach » thien thanh, hien hanh
nhung tung » nhung tuong, nhung dung, nhung vung
hien sach » dien sach, kien sach, chieu sach
quang cua » quan cua, quang tuan, quang huy
cua nhung » va nhung
tung dan » dung dan, huong dan, trung dai
dan than » dan chan, ban than, van than
than tap » toan tap, han tap, phan tap

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hien sach) or (thien hach)) - nhanh quang cua nhung tung dan than tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien sach) OR (thien hach)) - nhanh quang cua nhung tung dan than tap.
• Adding a wildcard symbol may retrieve word variants: hoc ((hien sach) or (thien hach)) - nhanh quang cua nhung tung dan than tap*.