Perhaps you should try some spelling variations:
thu nang » thi nang, thu hang, tho nang
tinh vai » tinh va, tinh hai, tinh bai
thu bang » thu ban, thu hang, chu bang
dan tinh » doan tinh, dang tinh, dan trinh
hieu van » hieu va, thien van, lieu va
cac nuoc » cap nuoc, hoc nuoc, cua nuoc
su sach » so sach, vu sach
vai cua » dai cua, hai cua, lai cua
cua te » cua tu

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 ((thu nang) OR (thu bang)) xa hoi. hieu van ((cac nuoc) or (dat nuoc)) dan tinh vai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((thu nang) OR (thu bang)) xa hoi. hieu van ((cac nuoc) OR (dat nuoc)) dan tinh vai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((thu nang) OR (thu bang)) xa hoi. hieu van ((cac nuoc) or (dat nuoc)) dan tinh vai cua te".
• Adding a wildcard symbol may retrieve word variants: su sach ((thu nang) OR (thu bang)) xa hoi. hieu van ((cac nuoc) or (dat nuoc)) dan tinh vai cua te*.